feat(desktop): wire updater endpoint to self-hosted Gitea + document Tauri WS origin

Point the Tauri updater at the real self-hosted Gitea "latest release" path:
https://git.infra.msai.al/mca/parking_solution/releases/latest/download/latest.json
— redirects to the newest tag's latest.json published by release.yml. Verified
against tauri-plugin-updater: it GETs the endpoint (200 + manifest / 204 = up to
date) and reads platforms.linux-x86_64.{signature,url}.

Document the desktop WS origin: the Tauri window loads from tauri://localhost
(Linux may also send http://tauri.localhost), which is NOT same-origin with the
backend, so WS_ALLOWED_ORIGINS must include both or the live feed won't connect.
Added both to apps/server/.env.example.

Updated the as-built in wiki/decisions/desktop-shell-tauri.md. Also carries an
unrelated plans.namePlaceholder copy tweak already in the tree. turbo build lint
14/14 green.

Claude-Session: https://claude.ai/code/session_01Xcm6ikLgGoCxxHrxtjkk5V

apps/server/.env.example

@@ -28,7 +28,10 @@ EVENT_SIGNING_KEY=
 
 # Comma-separated extra origins allowed to open the booth WebSocket (/api/ws).
 # In dev, set the Vite SPA origin. Same-origin is always allowed without this.
-WS_ALLOWED_ORIGINS=http://localhost:5173
+# The Tauri DESKTOP shell loads from tauri://localhost (Linux may also send
+# http://tauri.localhost), which is NOT same-origin with the backend — add both
+# so the desktop app's live feed connects. See apps/desktop.
+WS_ALLOWED_ORIGINS=http://localhost:5173,tauri://localhost,http://tauri.localhost
 
 # Vision / ANPR (optional) -------------------------------------------------
 # OFF by default. The Node SERVER's view of the vision microservice (apps/vision),