refactor: rename service to autostart, fix fork bomb, add rfd file picker, use dirs crate, auto-start launcher, propagate overlays, ensure icon

- Rename service module to autostart (no systemd service is used)
- Fix fork bomb: replace subprocess spawning with thread::spawn
- Replace zenity/kdialog with rfd crate for XDG Portal file picker
- Use dirs crate instead of env::var("HOME")
- Auto-start launcher before game launch for online auth
- Propagate gamemode/mangohud env vars to launcher process
- Auto-install SVG icon on startup via ensure_icon()
- Add assets/umutray.svg
- Remove stale zenity/kdialog optdepends from PKGBUILD
- Update .gitignore for .claude/ and CLAUDE.md

README.md

@@ -28,7 +28,7 @@ Launch / Kill entries. Users can add or remove launchers in `config edit`.
   (no ~600 MB in-memory buffering), with a progress indicator.
 - `diagnose` — sanity-checks umu-run, Vulkan, display server, per-launcher
   prefix / exe / ownership / running state.
-- `service` — installs an XDG autostart entry so the tray autostarts with
+- `autostart` — manages the XDG autostart entry so the tray starts with
   the graphical session.
 - `setup` — graphical wizard (iced) that downloads an installer URL
   (with progress bar) or accepts a local `.exe`, then runs it via
@@ -51,7 +51,7 @@ sudo pacman -S umu-launcher vulkan-tools
 Then enable autostart:
 
 ```sh
-umutray service install
+umutray autostart install
 ```
 
 ## Usage
@@ -79,9 +79,9 @@ umutray service install
 | `umutray config add-game …`      | Attach a game to a launcher (needs `--exe-path`)        |
 | `umutray config remove-game …`   | Drop a game from a launcher                             |
 | `umutray config set-game-flags …`| Per-game overlay toggles: gamemode/mangohud/gamescope   |
-| `umutray service install`        | Write XDG autostart entry (tray starts on login)        |
-| `umutray service uninstall`      | Remove the autostart and desktop entries                |
-| `umutray service status`         | Show whether XDG autostart is enabled                   |
+| `umutray autostart install`      | Write XDG autostart entry (tray starts on login)        |
+| `umutray autostart uninstall`    | Remove the autostart and desktop entries                |
+| `umutray autostart status`       | Show whether XDG autostart is enabled                   |
 
 ## Config