feat: implement shared-album multi-user photo album

Backend (Go/Gin/pgx): env config, pgx pool with retries, Garage S3 client
(path-style, region garage), embedded golang-migrate migrations, JWT auth with
refresh rotation, albums CRUD, members/roles/invites with no-escalation matrix,
photo upload + async imaging/goexif WebP variants, cursor pagination, presigned
URLs, likes/comments, SSE hub (album + personal), notifications, share links.

Frontend (SvelteKit 2 + Svelte 5 + Tailwind v4): API wrapper with 401 refresh,
auth store, all screens, Uploader/PhotoGrid/Lightbox/Comments, SSE client with
reconnect + REST catch-up, three themes + system via data-theme.

Deploy without Docker: Makefile builds the frontend into backend/static and
embeds it (go:embed) into a single statically linked binary; systemd unit and
nginx SSE example included.

Use gen2brain/webp (-tags nodynamic) instead of cgo kolesa-team/go-webp to keep
CGO_ENABLED=0 static builds; design.md/proposal.md updated accordingly.

frontend/package.json

@@ -0,0 +1,23 @@
+{
+  "name": "shared-album-frontend",
+  "private": true,
+  "version": "0.0.1",
+  "type": "module",
+  "scripts": {
+    "dev": "vite dev",
+    "build": "vite build",
+    "preview": "vite preview",
+    "check": "svelte-kit sync && svelte-check --tsconfig ./tsconfig.json"
+  },
+  "devDependencies": {
+    "@sveltejs/adapter-static": "^3.0.6",
+    "@sveltejs/kit": "^2.8.0",
+    "@sveltejs/vite-plugin-svelte": "^4.0.0",
+    "@tailwindcss/vite": "^4.0.0",
+    "svelte": "^5.1.0",
+    "svelte-check": "^4.1.0",
+    "tailwindcss": "^4.0.0",
+    "typescript": "^5.7.0",
+    "vite": "^5.4.0"
+  }
+}