feat(desktop): Tauri mac shell around the web export

Black screen root cause: Tauri injects nonces into style-src, which
makes WebKit drop 'unsafe-inline' and block react-native-web's inline
style attributes. style-src is now excluded from CSP modification.
Window opens on the home screen so the section menu is reachable.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Wmf3K9nCoEsXvvwkmMnuiM

desktop/src-tauri/src/main.rs

@@ -0,0 +1,22 @@
+// GTD desktop shell — Tauri 2 backend.
+//
+// The UI is the Expo web export (rebuilt from `app/` by
+// `scripts/export-web.sh` into `app/dist`, which this crate bundles via
+// `frontendDist`). All app logic, offline queueing, and API sync live in
+// that frontend; Rust only hosts the window. Native hooks (global
+// quick-add, menu-bar toggle) can attach to the builder below later
+// without touching the web code.
+//
+// CSP note (tauri.conf.json > app.security): `dangerousDisableAssetCspModification`
+// lists "style-src" because Tauri otherwise injects nonces into that directive,
+// which makes WebKit ignore 'unsafe-inline' and block every react-native-web
+// inline `style=""` attribute plus Reanimated's runtime <style> tags. The
+// result is a collapsed, unstyled page — a black screen in dark mode.
+// script-src still receives Tauri's hashes/nonces.
+#![cfg_attr(not(debug_assertions), windows_subsystem = "windows")]
+
+fn main() {
+    tauri::Builder::default()
+        .run(tauri::generate_context!())
+        .expect("failed to run GTD");
+}