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/test_meow_ui_widgets.c

@@ -5,7 +5,7 @@
  *   gcc -o test_meow_ui_widgets test_meow_ui_widgets.c test_host_stub.c \
  *       meow_ui_gfx.c meow_ui_sys.c meow_ui_theme.c meow_ui_vol.c meow_ui_log.c \
  *       meow_ui_widget.c meow_ui_input.c meow_ui_activity.c meow_ui_dialog.c meow_ui_ime.c \
- *       meow_ui_draw.c meow_ui_view.c meow_ui_img.c stb_image.c \
+ *       meow_ui_draw.c meow_ui_view.c meow_ui_img.c meow_notify_ipc.c stb_image.c \
  *       -I. -I../meow_launcherd -DMEOW_UI_HOST_TEST -pthread -lm
  * 运行：MEOW_UI_DUMP=/tmp/b2.ppm ./test_meow_ui_widgets   （可选，dump 屏幕）
  *