ui: PWA support (#23871)

ui: PWA support (#23871)

* feat: Add basic PWA support and service worker for offline caching

* feat: Vite PWA implementation WIP

* feat: Improve PWA icons generation

* feat: Add PWA workbox to server routes

* feat: Include `version.json` in static assets

* feat: Add HTTP cache headers for PWA static assets

* feat: Update app name for `apple-mobile-web-app-title`

* feat: Implement PWA versioning and automatic update detection

* chore: Update `.gitignore` files

* feat: Splash Screens

* feat: Add dark mode favicon support

* refactor: Cleanup

* fix: Use dark logo for dark splash screens

* refactor: Simplify favicons SVG code

* fix: Adjust caching and polling for reliable service worker updates

* fix: Add missing favicon entry

* fix: Align PWA service worker configuration with SvelteKit build structure

* fix: Replace hashed bundle paths with versioned static paths

* test: Add PWA tests

* ci: Add build output for unit tests

* refactor: Cleanup

* fix: Server build & release versioning

* chore: Update package-lock.json

* chore: Increase PWA cache size

* chore: Update packages

* feat: Update favicons

* refactor: Post-merge fix

* feat: support explicit build version for PWA cache busting

* fix: CI

* feat: Improve PWA Refresh Alert UI

* feat: Add toggleable build version display

* refactor: Cleanup

* feat: Add version mismatch detection and manual app reload

* refactor: replace dynamic imports with static

* refactor: Cleanup

* feat: Add safe space for `pwa-<size>.png` rendered icons

* fix: use relative paths for PWA assets to support base path deployment

* feat: add PWA mode detection via URL query parameter

* feat: Use ?cache=true for SW-cached PWA assets

* refactor: Build process cleanup

* refactor: Decouple PWA versioning and remove ?cache=true workaround

* chore: Update README logo

* feat: Include PWA Assets generation in build script

* refactor: `usePwa` hook for core layout

* fix: Relativize base vite plugin

* fix: remove unnecessary backslash escapes in test regexes

* test: update static asset paths for API Key test

* refactor: Move SvelteKit PWA Options config to constants

* ui: fix update notification never appearing

Keep the PWA hook object intact instead of destructuring needRefreshByStorage,
which freezes the reactive getter. Also exclude loading.html from PWA
precache to prevent 404 errors and broken SW installation.