ci(release): M139 发布 CI 只跑两个 Windows 槽位，整表六槽位改为手动取证

build 矩阵从六个槽位裁到 windows-x64 / windows-arm64 两个：
- 矩阵改由新增的 `plan` job 生成（`fromJSON(needs.plan.outputs.matrix)`），槽位表只在该
  job 里有一份，`mode: ci` 默认编、`mode: probe` 只有 `all_slots=true` 才编；
- `workflow_dispatch` 新增 `all_slots` 布尔输入（默认 false = 只跑 Windows），
  Linux/macOS 四档保留完整定义与打开办法（改 mode 一行），取证能力没删；
- `PUBLISH_SLOTS` 不变（两个 Windows 槽位）；齐全性检查仍按下载下来的产物判，
  白名单槽位没编/编挂就 fail，不会因矩阵变小而永远过；
- packaging/README.md §1/§3/§4/§9 与 release-notes.md 的 Downloads / Support matrix
  同步成「四档默认不构建」，不留「六槽位都构建」的旧说法。

packaging/release-notes.md

@@ -14,10 +14,12 @@ Asset names are `<name>_<version>_<platform>_<arch>`, underscore separated — t
 | Windows 10/11 x64 | `unlucky-launcher_{{VERSION}}_windows_x64.exe` | single exe, double-click to run |
 | Windows 11 ARM64 | `unlucky-launcher_{{VERSION}}_windows_arm64.exe` | single exe, runs natively on ARM64 Windows |
 
-**This release ships Windows only.** The Linux (x64 / arm64) and macOS (Apple Silicon / Intel) slots are
-built by CI but are not assets of this release: they have not been verified on real machines yet, so
-nothing unverified is handed out. They stay out of the download list and out of `SHA256SUMS.txt` until
-that verification happens — the support matrix below marks them accordingly.
+**This release ships Windows only, and CI builds Windows only.** The Linux (x64 / arm64) and macOS
+(Apple Silicon / Intel) slots are not built by the release workflow at all — they have not been verified
+on real machines yet, so nothing unverified is handed out and no build minutes are spent on them. They
+stay out of the download list and out of `SHA256SUMS.txt` until that verification happens; a manual
+workflow run can build all six slots for that purpose, but the four extra slots are never published. The
+support matrix below marks those slots accordingly.
 
 The Windows assets are bare `.exe` files, so `LICENSE`, `NOTICE` and `README.md` are attached to this
 release next to them: the license terms travel with every download. Slots that ship an archive (Linux /
@@ -45,19 +47,19 @@ Published = shipped as a download of **this** release, listed in `SHA256SUMS.txt
 | --- | --- | --- | --- |
 | Windows 10/11 x64 | **published** | first class | nothing beyond the OS (UCRT is part of Win10+) |
 | Windows 11 ARM64 | **published** | first class (launcher artifact) | nothing extra; the launcher runs natively, the game itself runs through the OS x64 emulation layer with an x64 JDK |
-| macOS 12+ Apple Silicon | built by CI, not published | first class (unverified) | nothing; unsigned build, needs the Gatekeeper workaround |
-| macOS 12+ Intel | built by CI, not published | first class (unverified) | same as above |
-| Linux x64, X11 | built by CI, not published | first class (unverified) | `libxkbcommon`, `fontconfig`, `libGL` (or software renderer), `libxcb` |
-| Linux x64, Wayland | built by CI, not published | supported (unverified) | `wayland-client`, `libxkbcommon`, plus the X11 set for XWayland apps |
-| Linux arm64, X11 | built by CI, not published | first class (unverified) | glibc 2.35+, `libxkbcommon`, `fontconfig`, `libGL`, `libxcb` |
-| Linux arm64, Wayland | built by CI, not published | supported (unverified) | the above plus `wayland-client` |
+| macOS 12+ Apple Silicon | not built (unverified) | first class (unverified) | nothing; unsigned build, needs the Gatekeeper workaround |
+| macOS 12+ Intel | not built (unverified) | first class (unverified) | same as above |
+| Linux x64, X11 | not built (unverified) | first class (unverified) | `libxkbcommon`, `fontconfig`, `libGL` (or software renderer), `libxcb` |
+| Linux x64, Wayland | not built (unverified) | supported (unverified) | `wayland-client`, `libxkbcommon`, plus the X11 set for XWayland apps |
+| Linux arm64, X11 | not built (unverified) | first class (unverified) | glibc 2.35+, `libxkbcommon`, `fontconfig`, `libGL`, `libxcb` |
+| Linux arm64, Wayland | not built (unverified) | supported (unverified) | the above plus `wayland-client` |
 | Windows 8.1/8/7 | not built | unsupported | the baseline is Windows 10 |
 | Android — Termux + X11 | not built (no CI slot) | experimental, not promised | CLI only and only when built from source; GUI unverified |
 
 Both arm64 rows are formal matrix slots, not the experimental Termux path: Windows ARM64 ships here and
-is cross-built with the same static-CRT gate as x64; Linux arm64 builds on a native ARM64 runner and
-joins this list once someone has run it on real hardware. The rows above and the matrix table in
-`packaging/README.md` §9 are the same list — change one, change the other.
+is cross-built with the same static-CRT gate as x64; Linux arm64 is kept as a matrix slot but is not built
+by default — someone has to run it on real hardware (via a manual all-slots run) before it joins this list.
+The rows above and the matrix table in `packaging/README.md` §9 are the same list — change one, change the other.
 
 ## Install