feat(sdk+launcher): SDK nav/media封装 + §10.5 App前台唤起通知中心 (agent-206) — meow_ui_nav.c(env栈初始化+report/request_exit) + meow_ui_media.c(懒连断线重连, meta上报+playctl接收) + MSG_NOTIF_OPEN=0x28/CLOSE=0x29(0x25/26已被占); SDK顶部下滑手势→IPC; launcher App前台会话叠加通知中心(SIGSTOP→读帧→接管输入→恢复SIGCONT, 面板内App崩溃即关); hello接线验证

meow_ui.a→9a8eb7ef; hello→fc299577; launcher→b33da20a; 宿主5套件+新test_notif_open+qemu分发 全过
出入: SDK符号用meow_ui_前缀防与launcher内同名冲突; 叠加会话真机待验; §10.5文档旧号段已过时

patch_v2/sdk/meow_ui_nav.c

@@ -0,0 +1,74 @@
+/* meow_ui_nav.c — App 侧 M3 导航上报封装（SDK 公共件；见 meow_ui_nav.h）。
+ *
+ * 只做「组装 m_nav_t + 经 meow_notify_ipc 一次性发送 MSG_NAV」，不维护连接/订阅循环；
+ * launcher 主循环单写者消费（回复 ACK）。全部失败路径优雅降级（无 socket/写失败/超时
+ * → 静默返回，不崩）。状态（栈深/顶层/app_id）仅进程内缓存，无并发写（App 页面线程调用）。
+ */
+#include "meow_ui_nav.h"
+#include "meow_ipc.h"
+#include "meow_notify_ipc.h"   /* meow_notify_ipc_send_raw（复用其一次性帧传输层） */
+
+#include <stdlib.h>
+#include <string.h>
+#include <stdio.h>
+
+static char g_app_id[MEOW_APP_ID_MAX] = "";
+static int  g_depth = 0;
+static char g_top[MEOW_ACT_MAX] = "";
+static int  g_inited = 0;
+
+/* app_id：env MEOW_LOG_APP（与 meow_ui_log/meow_notify_ipc 取值口径一致），缺省 "app"。 */
+static const char *nav_app_id(void)
+{
+    if (!g_app_id[0]) {
+        const char *s = getenv("MEOW_LOG_APP");
+        snprintf(g_app_id, sizeof g_app_id, "%s", (s && s[0]) ? s : "app");
+    }
+    return g_app_id;
+}
+
+int meow_ui_nav_init(void)
+{
+    if (g_inited) return g_depth;
+    g_inited = 1;
+    nav_app_id();
+    const char *chain = getenv("MEOW_CHAIN");
+    if (chain && chain[0]) {
+        g_depth = 1;
+        for (const char *p = chain; *p; p++) if (*p == ';') g_depth++;
+    }
+    const char *act = getenv("MEOW_ACTIVITY");
+    if (act && act[0]) snprintf(g_top, sizeof g_top, "%s", act);
+    return g_depth;
+}
+
+int meow_ui_nav_depth(void) { meow_ui_nav_init(); return g_depth; }
+const char *meow_ui_nav_top(void) { meow_ui_nav_init(); return g_top; }
+
+void meow_ui_nav_report(uint32_t depth, const char *top)
+{
+    meow_ui_nav_init();
+    m_nav_t n;
+    memset(&n, 0, sizeof n);
+    snprintf(n.app_id, sizeof n.app_id, "%s", nav_app_id());
+    n.nav_type = MEOW_NAV_REPORT;
+    n.depth = depth;
+    if (top) snprintf(n.current, sizeof n.current, "%s", top);
+    (void)meow_notify_ipc_send_raw(MSG_NAV, &n, (uint32_t)sizeof n, 1);
+    /* 进程内镜像：App 侧也维持当前栈深/顶层（跨 TU 只读用） */
+    g_depth = (int)depth;
+    if (top) snprintf(g_top, sizeof g_top, "%s", top);
+}
+
+void meow_ui_nav_request_exit(void)
+{
+    meow_ui_nav_init();
+    m_nav_t n;
+    memset(&n, 0, sizeof n);
+    snprintf(n.app_id, sizeof n.app_id, "%s", nav_app_id());
+    n.nav_type = MEOW_NAV_EXIT;
+    n.depth = 0;
+    (void)meow_notify_ipc_send_raw(MSG_NAV, &n, (uint32_t)sizeof n, 1);
+    g_depth = 0;
+    g_top[0] = 0;
+}