merge(dev): 解 M196 与 dev（M179/M193）在 settings/mod.rs 的冲突

`origin/main` 是 D41 的孤儿快照（单提交、与开发史无共同祖先），M179/M193 这些提交在
`origin/dev` 上；按「跟上主线」的意图合的是 `origin/dev`。用 merge 不用 rebase：复审 clean 的
tip `e5a4b9b` 原样保留，本提交只负责解冲突。

唯一冲突：`settings/mod.rs` 里 `form` 的文档注释（M179 与 M195 重写过同一段）。两边都留：
- **M179/M193**：`type Body` 带 `Lang`、四条按下标分发（General / Update / Assistant / Java）、
  M193 的 download / logs 接线及其文档更新——只有一处措辞随之调整：「四组在下面各有 `else if`」
  → 「在 [`section_columns`] 里各有 `else if`」，因为 M195 把那层循环抽成了独立函数；
- **M195**：循环之后不再 push 那张「没有逐实例覆盖」的空态卡、`overrides_empty` 不存在、
  `section_columns` 与其行为断言（`frame.rs` 两条用例）。
合并后的注释同时说明两件事：`GROUP.body` 从形参拿生效语言（M179）+ 尾部不许再挂东西、
逐实例覆盖的真控件在实例详情页（M195）。

为守住 400 行硬线（冲突态 424 → 399），只压自己的重复叙述：M196 段压到 4 行、
`section_columns` 的文档改为指向 `form`（它原来重复了一遍分发点，且在 M179 之后已不准确）、
模块文档里一段被 M179 实现取代的历史「r3 订正」压成一句可执行的结论。

代码零语义改动（证据见汇报）：`section_columns` 的循环体与 `origin/dev` 归一化后逐字节相同（46 行），
`GROUPS` / `GROUP_LABELS` 三方一致；相对 `origin/dev` 的差异只剩本 mission 的 4 个文件。

crates/i18n/src/catalog/golden/tail.rs

@@ -24,11 +24,117 @@ pub(super) const ROWS: &[(&str, &str, &str)] = &[
     ("FontCjkReady", "Chinese font ready: {family}", "中文字体已就绪：{family}"),
     ("SettingsLanguage", "Language", "界面语言"),
     ("SettingsLanguageHint", "Switches the interface language. Chinese text needs a Chinese font.", "切换界面语言。显示中文需要中文字体。"),
+    ("SettingsLogsFolder", "Log folder", "日志文件夹"),
+    ("SettingsLogsFolderHint", "What explains a crash lives here: the launcher's own runtime log (launcher.log, rolled over at 1 MiB with one old copy kept) and one jsonl per game session under logs/game/. Sessions from older versions (data/agent/sessions) are still read, not moved.", "解释一次崩溃要看的东西都在这：启动器自己的运行日志（launcher.log，满 1 MiB 滚动一次、只留一份旧档）与每次游戏会话的 jsonl（logs/game/）。旧版本留下的会话（data/agent/sessions）仍然读得出来，不会被搬动。"),
+    ("SettingsLogsCopy", "Copy path", "复制路径"),
+    ("SettingsLogsUnknown", "Data directory not resolved — restart the launcher from its own folder", "数据根没解析出来——从启动器所在目录重新启动试试"),
     ("SettingsAppearanceCorner", "Window corners", "窗口圆角"),
     ("SettingsAppearanceCornerSystem", "Follow system", "跟随系统"),
     ("SettingsAppearanceCornerSquare", "Square", "直角"),
     ("SettingsAppearanceCornerHint", "On Windows 11 and Server 2025 we ask the system for rounded corners; Windows 10 keeps square corners. On macOS and Linux the desktop's own rules apply. We never draw corners ourselves.", "Windows 11 与 Windows Server 2025 上我们请求系统处理外框圆角；Windows 10 保持直角；macOS 与 Linux 交给桌面合成器自己的规则；我们不自己画圆角。"),
     ("SettingsAppearanceCornerSuspended", "Not in effect right now: window transparency is below 100%. Setting it back to 100% restores the rounded corners.", "当前因整窗透明度不生效：把整窗透明度调回 100% 圆角即恢复。"),
+    // M180：外观分组补齐（`catalog/settings/appearance.rs` 的第二批，M116 圆角那 5 条之后）。
+    // 位置就是装配链里那个域的位置——`settings_appearance_entries` 在 `settings_java_entries` 之前，
+    // 所以这 40 行必须落在 `SettingsAppearanceCornerSuspended` 与 `SettingsJavaScan` 之间
+    // （顺序 = `Key::ALL`；为排到文件尾而重排别人的族会让 `split_keeps_every_translation` 整片红）。
+    ("SettingsAppearanceWindowOpacity", "Window transparency", "整窗透明度"),
+    ("SettingsAppearanceWindowOpacityHint", "Applies to the whole window. Floor {floor}; 1.00 = fully opaque.", "作用于整个窗口。下限 {floor}；1.00 = 完全不透明。"),
+    ("SettingsAppearancePanelOpacity", "Panel transparency", "面板透明度"),
+    ("SettingsAppearancePanelOpacityHint", "Only the panel/card layer. Floor {floor}; independent of window transparency.", "只作用于面板 / 卡片这一层。下限 {floor}；与整窗透明度互不影响。"),
+    ("SettingsAppearancePanelOpacityForcedValue", "100% (forced from {requested})", "100%（强制，原请求值 {requested}）"),
+    ("SettingsAppearancePanelOpacityForcedHint", "Software renderer: panels and glass stay fully opaque (window transparency still works).", "软件渲染：面板与玻璃效果恒为不透明（整窗透明度仍然有效）。"),
+    ("SettingsAppearanceBackgroundImage", "Background image", "背景图"),
+    ("SettingsAppearanceOff", "Off", "关"),
+    ("SettingsAppearanceOn", "On", "开"),
+    ("SettingsAppearanceImagePath", "Image path", "图片路径"),
+    ("SettingsAppearancePaletteLevel", "Colours: {level}", "配色：{level}"),
+    ("SettingsAppearanceBgFill", "Fill", "填充方式"),
+    ("SettingsAppearanceBgFillCover", "Cover", "铺满"),
+    ("SettingsAppearanceBgFillContain", "Contain", "完整显示"),
+    ("SettingsAppearanceBgFillTile", "Tile", "平铺"),
+    ("SettingsAppearanceBgDim", "Dim", "暗化"),
+    ("SettingsAppearanceBgDimHint", "Blends the image toward the panel colour so text stays readable. Max {max}.", "把背景图往面板底色上退，让文字读得清。上限 {max}。"),
+    ("SettingsAppearancePaletteSource", "Colour source", "配色来源"),
+    ("SettingsAppearancePaletteBackground", "Background", "取自背景图"),
+    ("SettingsAppearancePaletteWallpaper", "Wallpaper", "取自壁纸"),
+    ("SettingsAppearancePalettePreset", "Preset", "内置色卡"),
+    ("SettingsAppearanceBgReadFailed", "Background image could not be read: {reason}", "背景图读不出来：{reason}"),
+    ("SettingsAppearanceBgDecodeFailed", "Background image could not be decoded ({reason}; this build decodes PNG, JPEG and BMP)", "背景图解不开（{reason}；这个构建只支持 PNG、JPEG 与 BMP）"),
+    ("SettingsAppearanceBgTooLarge", "Background image is too large to decode: {width}×{height} (limit {limit} px per edge)", "背景图太大，解不开：{width}×{height}（每边上限 {limit} 像素）"),
+    ("SettingsAppearanceBgSmallTile", "Small image ({width}×{height}): tiles are scaled up so the window stays covered (max {max} tiles, no gaps).", "图片很小（{width}×{height}）：图块会被放大，保证窗口铺满（最多 {max} 块，不留缝）。"),
+    ("SettingsAppearancePaletteBgUndecodable", "Background image could not be read; colours fall back.", "背景图读不出来，配色回落到下一级。"),
+    ("SettingsAppearancePaletteBgTooSmall", "Background image is too small to sample; colours fall back.", "背景图太小，取不了色，配色回落到下一级。"),
+    ("SettingsAppearancePaletteBgBadDimensions", "Background image data looks inconsistent; colours fall back.", "背景图数据前后不一致，配色回落到下一级。"),
+    ("SettingsAppearancePaletteBgNoOpaquePixels", "Background image is almost fully transparent; colours fall back.", "背景图几乎全透明，配色回落到下一级。"),
+    ("SettingsAppearancePaletteBgLowChroma", "Background image is too monochrome to tint from; colours fall back.", "背景图太单调（彩度不足），取不出配色，回落到下一级。"),
+    ("SettingsAppearancePaletteBgContrast", "Background image colours would be unreadable; colours fall back.", "按背景图取的颜色读不清，配色回落到下一级。"),
+    ("SettingsAppearancePaletteWallpaperUndecodable", "Desktop wallpaper could not be read.", "桌面壁纸读不出来。"),
+    ("SettingsAppearancePaletteWallpaperTooSmall", "Desktop wallpaper is too small to sample.", "桌面壁纸太小，取不了色。"),
+    ("SettingsAppearancePaletteWallpaperBadDimensions", "Desktop wallpaper data looks inconsistent.", "桌面壁纸数据前后不一致。"),
+    ("SettingsAppearancePaletteWallpaperNoOpaquePixels", "Desktop wallpaper is almost fully transparent.", "桌面壁纸几乎全透明。"),
+    ("SettingsAppearancePaletteWallpaperLowChroma", "Desktop wallpaper is too monochrome to tint from.", "桌面壁纸太单调（彩度不足），取不出配色。"),
+    ("SettingsAppearancePaletteWallpaperContrast", "Desktop wallpaper colours would be unreadable; colours fall back.", "按桌面壁纸取的颜色读不清，配色回落到下一级。"),
+    ("SettingsAppearancePalettePresetContrast", "The built-in card needed a small contrast correction.", "内置色卡做了一点对比度修正。"),
+    ("SettingsAppearancePaletteAdjusted", "A few colours were nudged for readability.", "有几个颜色为了可读性做了微调。"),
+    // M175：设置页「Java」分组（`catalog/settings/java.rs` 的 `settings_java_entries`）。
+    // 位置就是装配链里那个域的位置：`settings_java_entries` 在 `settings_appearance_entries` 之后、
+    // `settings_download_entries`（空）与 `settings_ai_entries`（M174）之前，所以这几行必须落在
+    // `SettingsAppearanceCornerSuspended` 与 `SettingsGroupAssistant` 之间（顺序 = `Key::ALL`）。
+    ("SettingsJavaScan", "Scan now", "立即扫描"),
+    ("SettingsJavaScanningStart", "Scanning…", "正在扫描…"),
+    ("SettingsJavaScanning", "Scanning… {done}/{total}", "正在扫描… {done}/{total}"),
+    ("SettingsJavaCancelling", "Cancelling…", "正在取消…"),
+    ("SettingsJavaCancel", "Cancel", "取消"),
+    ("SettingsJavaCancelled", "The scan was cancelled; the list below is from the previous run.", "扫描已取消；下面的列表还是上一次的结果。"),
+    ("SettingsJavaScanDone", "{count} JDK found", "找到 {count} 个 JDK"),
+    ("SettingsJavaNeverScanned", "Not scanned yet", "还没扫描过"),
+    ("SettingsJavaNeverScannedBody", "Press Scan to look for installed JDKs (registry, common install folders, JAVA_HOME and PATH). Nothing runs until you do.", "点「立即扫描」去找已装的 JDK（注册表、常见安装目录、JAVA_HOME 与 PATH）。在那之前启动器不会自己去扫。"),
+    ("SettingsJavaEmptyTitle", "No Java runtime found", "未检测到 Java 运行时"),
+    ("SettingsJavaEmptyBody", "Nothing matched. Add the path of a JDK you already unpacked below, or install one with `ull java install 21` on the command line.", "没找到任何 JDK。可以在下面手动加上你自己解压的那份，或者用命令行 `ull java install 21` 装一个。"),
+    ("SettingsJavaDefault", "Default", "默认"),
+    ("SettingsJavaSetDefault", "Use as default", "设为默认"),
+    ("SettingsJavaFits", "Meets the current instance requirement", "满足当前实例的要求"),
+    ("SettingsJavaTooOld", "Below the requirement: this instance needs Java {minimum}+", "低于要求：当前实例需要 Java {minimum} 及以上"),
+    ("SettingsJavaDefaultSet", "Default JDK is now {path}", "默认 JDK 已设为 {path}"),
+    ("SettingsJavaSourceManaged", "installed by this launcher", "本启动器安装"),
+    ("SettingsJavaSourceEnv", "JAVA_HOME (environment variable)", "JAVA_HOME（环境变量）"),
+    ("SettingsJavaSourcePath", "on PATH", "PATH 上"),
+    ("SettingsJavaSourceSystem", "system install", "系统安装"),
+    ("SettingsJavaSourceManual", "added by you", "手动添加"),
+    ("SettingsJavaAdd", "Add a JDK path", "手动添加 JDK 路径"),
+    ("SettingsJavaAddPlaceholder", "C:\\Program Files\\Java\\jdk-21", "例：C:\\Program Files\\Java\\jdk-21"),
+    ("SettingsJavaAddHint", "A JDK folder or its java executable. We run `java -version` on it; anything that cannot answer is refused.", "JDK 目录或它的 java 可执行文件。会真跑一次 `java -version`；答不出话的一律拒绝。"),
+    ("SettingsJavaAddAction", "Add", "添加"),
+    ("SettingsJavaAdded", "Added {path}", "已添加 {path}"),
+    ("SettingsJavaMemory", "Default memory (MB)", "默认内存（MB）"),
+    ("SettingsJavaMemoryHint", "Whole megabytes, {min}–{max}. Instances without their own override follow this value.", "整数 MB，范围 {min}~{max}。没有实例级覆盖的实例都用它。"),
+    ("SettingsJavaLayerGlobal", "In effect: {mb} MB, from the global default.", "生效：{mb} MB，来自全局默认值。"),
+    ("SettingsJavaLayerInstance", "In effect: {mb} MB, set by instance {instance}. Changing the global value below will not affect that instance.", "生效：{mb} MB，由实例 {instance} 覆盖。改下面的全局值不会影响它。"),
+    ("SettingsJavaJvm", "Extra JVM arguments", "额外 JVM 参数"),
+    ("SettingsJavaJvmPlaceholder", "-XX:+UseG1GC -Dfile.encoding=UTF-8", "例：-XX:+UseG1GC -Dfile.encoding=UTF-8"),
+    ("SettingsJavaJvmHint", "Separated by spaces, quotes allowed. Appended to the command line of every launch; an instance's own JVM arguments come after it.", "按空白分隔，支持引号。会拼到每次启动的命令行上；实例自己的 JVM 参数排在它后面。"),
+    ("SettingsJavaJvmSaved", "Saved value: {value}", "已保存的值：{value}"),
+    ("SettingsJavaJvmSavedNone", "No extra JVM arguments are saved yet.", "还没有保存任何额外参数。"),
+    ("SettingsJavaSave", "Save", "保存"),
+    ("SettingsJavaSaved", "Saved and read back from disk. The next launch uses the new value.", "已保存，并从磁盘读回确认。下次启动就用新值。"),
+    ("SettingsJavaUnsaved", "There are unsaved changes.", "有未保存的改动。"),
+    ("SettingsJavaRefused", "Not saved: {reason}", "未保存：{reason}"),
+    ("SettingsJavaSkipNotDirty", "there was nothing to change, so no file was written", "没有任何改动，因此没有写文件"),
+    ("SettingsJavaSkipReadOnly", "the settings file is read-only: a newer launcher wrote it, or it is marked untrusted", "配置文件只读：它被更新版本的启动器写过，或被标记为不可信"),
+    ("SettingsJavaSkipUnreadable", "the settings file is untrusted, so it is treated as read-only", "配置文件不可信，因此按只读处理"),
+    ("SettingsJavaNoStorage", "No settings file is available in this run, so nothing can be scanned or saved.", "这一次运行没有可用的设置文件，扫描与保存都做不了。"),
+    ("SettingsJavaReasonMemoryEmpty", "the memory field is empty", "内存没填"),
+    ("SettingsJavaReasonMemoryNotNumber", "the memory must be a whole number of MB", "内存必须是整数 MB"),
+    ("SettingsJavaReasonMemoryRange", "the memory is outside the allowed range", "内存超出允许范围"),
+    ("SettingsJavaReasonJvmQuotes", "the JVM arguments have an unclosed quote", "JVM 参数里有没配对的引号"),
+    ("SettingsJavaReasonAddEmpty", "the path is empty", "路径是空的"),
+    ("SettingsJavaReasonAddMissing", "nothing exists at that path", "那个路径上什么都没有"),
+    ("SettingsJavaReasonAddNotJava", "there is no java executable at that path", "那个路径里没有 java 可执行文件"),
+    ("SettingsJavaReasonAddNoVersion", "java -version did not answer there, so it is not a usable JDK", "在那里跑不出 java -version，不是一份能用的 JDK"),
+    ("SettingsJavaReasonAddTooLong", "the path is too long to be a JDK location", "路径太长，不像是一个 JDK 位置"),
+    ("SettingsJavaReasonAddWriteFailed", "the JDK is fine, but the list file could not be written (disk or permission)", "这份 JDK 没问题，但名单文件写不进去（磁盘或权限）"),
+    ("SettingsJavaReasonAddDuplicate", "that JDK is already in the list", "这份 JDK 已经在列表里了"),
+    ("SettingsJavaReasonWriteFailed", "the settings file could not be written (disk full, no permission, or the value was rejected)", "设置写不进去（磁盘满、没权限，或这个值被拒绝）"),
     // M174：设置页「助手（AI）」分组（`catalog/settings/ai.rs` 的 `settings_ai_entries`）。
     // 位置就是装配链里那个域的位置：`settings_ai_entries` 在 `settings_download_entries` 之后、
     // `core_text_entries` 之前，所以这几行必须落在 `SettingsAppearanceCornerSuspended` 与
@@ -142,6 +248,31 @@ pub(super) const ROWS: &[(&str, &str, &str)] = &[
     ("LogsEmptyTitle", "No output yet", "还没有输出"),
     ("LogsEmptyBody", "Logs stream here while the launcher or the game is running. Pick an instance and start it to see the first lines.", "启动器或游戏运行时，日志会实时出现在这里。选择一个实例并启动，就能看到第一批日志。"),
     ("LogsEmptyAction", "Choose an instance", "选择实例"),
+    ("CrashDialogTitleFailed", "Launch failed", "启动失败"),
+    ("CrashDialogTitleCrashed", "The game crashed", "游戏崩溃"),
+    ("CrashDialogExitCode", "Exit code {code}", "退出码 {code}"),
+    ("CrashDialogStartedThenDied", "The game process started, then exited abnormally.", "游戏进程起来了，随后异常退出。"),
+    ("CrashDialogSilentFailure", "The game exited with code 0 but never really started.", "游戏以退出码 0 结束，但并没有真正起来。"),
+    ("CrashDialogStageReason", "It failed before the game could start: {stage}", "游戏还没起来就失败了：{stage}"),
+    ("CrashDialogCrashReportFound", "The game wrote a crash report — the details are below.", "游戏写出了崩溃报告，详见下方说明。"),
+    ("CrashDialogNoGameLog", "No crash report this time: the game stopped before it could write one. The last lines the launcher captured are below.", "这次没有生成崩溃报告：游戏还没来得及写就停了。下面是启动器捕获的最后若干行。"),
+    ("CrashDialogNoLogAtAll", "No crash report and no captured output. Most likely: missing Java, not enough memory, wrong launch arguments, or missing libraries.", "既没有崩溃报告，也没有捕获到输出。最可能的原因：缺少 Java、内存不足、启动参数错误、或库文件缺失。"),
+    ("CrashDialogShowDetail", "Show crash details", "展开崩溃说明"),
+    ("CrashDialogHideDetail", "Hide crash details", "收起崩溃说明"),
+    ("CrashDialogLauncherLogs", "Launcher logs", "启动器日志"),
+    ("CrashDialogSessionLog", "This session", "本次会话"),
+    ("CrashDialogGameLog", "Game latest.log", "游戏 latest.log"),
+    ("CrashDialogCrashReports", "Crash reports", "崩溃报告目录"),
+    ("CrashDialogCapturedTail", "CAPTURED OUTPUT (last {count} lines)", "捕获输出（最后 {count} 行）"),
+    ("CrashDialogExport", "Export report bundle", "导出诊断包"),
+    ("CrashDialogOpenFolder", "Open log folder", "打开日志文件夹"),
+    ("CrashDialogCopyPaths", "Copy file paths", "复制文件路径"),
+    ("CrashDialogClose", "Close", "关闭"),
+    ("CrashDialogCopied", "File paths copied to the clipboard", "文件路径已复制到剪贴板"),
+    ("CrashDialogExportDone", "Exported {bytes} bytes to {path}", "已导出 {bytes} 字节到 {path}"),
+    ("CrashDialogExportFailed", "Export failed: {error}", "导出失败：{error}"),
+    ("CrashDialogExportTruncated", "{count} file(s) were too large and are truncated (head + tail kept).", "有 {count} 个文件太大，已截断（保留头 + 尾）。"),
+    ("CrashDialogOpenFailed", "Could not open the folder: {error}", "打不开文件夹：{error}"),
     ("AgentTitle", "Assistant", "助手"),
     ("AgentSubtitle", "Simulated assistant · no real model is connected", "模拟助手 · 还没接真实模型"),
     ("AgentCollapse", "Collapse", "收起"),
@@ -252,6 +383,11 @@ pub(super) const ROWS: &[(&str, &str, &str)] = &[
     ("ContentModpackNotReady", "Installing modpacks from the library into an instance is not available yet", "从内容库一键安装整合包到实例还没做（本地的包可以直接导入）"),
     ("ContentSourceUnavailable", "CurseForge needs an API key: add one in Settings", "CurseForge 需要在设置里配置密钥才能搜索"),
     ("ContentSourceNotWired", "Installing from CurseForge is not available yet", "CurseForge 来源的安装尚未开放"),
+    ("ContentInstallFailedTitle", "Install did not finish — {count} items failed", "安装未完成 —— {count} 项没装上"),
+    ("ContentInstallRetryIncompatible", "Not available for this version/loader", "不兼容所选版本/加载器"),
+    ("ContentInstallRetryUnreachable", "Could not fetch (network or missing project)", "取不到（网络 / 项目不存在）"),
+    ("ContentInstallRetryOnly", "Retry just these {count}", "只重试这 {count} 个"),
+    ("ContentInstallRetryHint", "Retry asks again only for the items above; files that already landed stay put.", "重试只重新解析上面这几项，已落盘的文件不动。"),
     ("PackTitle", "Modpack import & export", "整合包导入 / 导出"),
     ("PackImportTitle", "Import a modpack", "导入整合包"),
     ("PackDropHint", "Drop a .mrpack, .zip or a MultiMC/Prism instance folder here", "把 .mrpack / .zip 或 MultiMC·Prism 实例目录拖到这里"),
@@ -259,9 +395,4 @@ pub(super) const ROWS: &[(&str, &str, &str)] = &[
     ("PackNoDialog", "This build has no system file picker: drag the file in, or paste its path below.", "本版没有系统文件选择框：请把文件拖进来，或在下面粘贴路径。"),
     ("PackPathLabel", "Pack path", "整合包路径"),
     ("PackPathPlaceholder", "D:\\packs\\Better MC.mrpack", "D:\\整合包\\更好的MC.mrpack"),
-    ("PackImportAction", "Import", "导入"),
-    ("PackCancel", "Cancel import", "取消导入"),
-    ("PackDismiss", "Dismiss", "关闭"),
-    ("PackTargetLabel", "Install into", "装到实例"),
-    ("PackTargetNew", "New instance", "新建实例"),
 ];