Add setup tray entry, wizard progress/log, config add/remove, stale-wine check

- tray: uninstalled launchers now show a "Setup…" entry that spawns
  the setup wizard as a child process.
- setup.rs: download shows a progress bar (bytes / total), and
  umu-run stdout+stderr stream into a scrollable log pane. A 250 ms
  tick subscription pulls updates from the shared state.
- config add-launcher / remove-launcher CLI, with sensible defaults
  for prefix_dir, gameid, and process_pattern derived from name/exe.
- diagnose: flag stale wineserver processes when no launcher is
  running, suggesting `umutray kill`.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

Cargo.lock

@@ -1827,6 +1827,7 @@ dependencies = [
  "iced_core",
  "log",
  "rustc-hash 2.1.2",
+ "tokio",
  "wasm-bindgen-futures",
  "wasm-timer",
 ]