feat(native): Tier A desktop features (P5-46/36/44/43/49) + window chrome (P5-47)

Adds a `native/` module system (each feature = its own module exposing
`#[tauri::command]`s + optional `setup`; `emit_to_web` pushes DOM CustomEvents to
the web like `forward_deeplink`). Wired into generate_handler! + native::setup;
windows-crate feature union added to Cargo.toml.

- power.rs (P5-46): SetThreadExecutionState held on the main thread while a call
  is active; released on end. Cross-platform (no-op off Windows).
- jumplist.rs (P5-36): ICustomDestinationList "Recent Rooms" of IShellLink tasks
  launching the exe with a matrix: arg (existing deep-link handler opens the room).
- thumbbar.rs (P5-44): ITaskbarList3 ThumbBar Mute/Deafen/End (GDI HICONs) + a
  window subclass catching THBN_CLICKED → emit thumbbar-action.
- smtc.rs (P5-43): WinRT SystemMediaTransportControls via GetForWindow; ButtonPressed
  → smtc-action; call-state command. (Experimental for a non-media app.)
- network.rs (P5-49): INetworkListManager poll thread → emit network-changed.
- chrome.rs (P5-47): cross-platform window-control commands + set_custom_chrome
  (set_decorations) for the opt-in TDS titlebar.

NOT compile-verified locally (no Rust/Windows toolchain on the dev box) — this is
for the CI Windows compile pass (GitHub test.yml / Gitea windows runner). Expect a
possible fixup round (windows-crate feature/namespace paths, e.g. subclass APIs).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

src-tauri/Cargo.toml

@@ -48,9 +48,19 @@ tauri-plugin-single-instance = "2"
 webview2-com = "0.38"
 window-vibrancy = "0.6"
 windows = { version = "0.61", features = [
+    # WinRT namespaces (SMTC — P5-43)
+    "Foundation",
+    "Media",
+    # Win32 namespaces
+    "Win32_Foundation",
     "Win32_Graphics_Gdi",
+    "Win32_Networking_NetworkListManager", # P5-49 network awareness
     "Win32_System_Com",
+    "Win32_System_Com_StructuredStorage",  # P5-36 jump list (PROPVARIANT)
+    "Win32_System_Power",                  # P5-46 no-sleep
+    "Win32_System_WinRT",                  # P5-43 SMTC interop
     "Win32_UI_Shell",
+    "Win32_UI_Shell_PropertiesSystem",     # P5-36 jump list (IPropertyStore/PKEY_Title)
     "Win32_UI_WindowsAndMessaging",
 ] }