Initial commit: playlink music library hardlink deduplicator

Go backend (chi, SQLite) with an embedded React/TypeScript UI that finds
songs present in both a host and a slave music library and replaces the
slave copy with a hardlink to the host copy.

- Path-first matching with format/title/album-folder fallbacks
- Auto-linking of byte-identical files, re-verified with cmp before linking
- Manual review with ffprobe quality comparison, downgrade guard and
  promote-to-host override
- Build mode to populate an empty slave library from the host
- Dry run by default, atomic stage+rename replacement, quarantine with
  retention, undo, path confinement and authenticated UI
- Dockerfile and compose file for Unraid

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

web/package.json

@@ -0,0 +1,26 @@
+{
+  "name": "playlink-web",
+  "private": true,
+  "version": "0.1.0",
+  "type": "module",
+  "scripts": {
+    "dev": "vite",
+    "build": "tsc -b && vite build",
+    "typecheck": "tsc -b"
+  },
+  "dependencies": {
+    "@tanstack/react-query": "^5.103.2",
+    "lucide-react": "^1.47.0",
+    "react": "^19.3.0",
+    "react-dom": "^19.3.0"
+  },
+  "devDependencies": {
+    "@tailwindcss/vite": "^4.3.3",
+    "@types/react": "^19.3.0",
+    "@types/react-dom": "^19.3.0",
+    "@vitejs/plugin-react": "^6.1.1",
+    "tailwindcss": "^4.3.3",
+    "typescript": "^7.0.2",
+    "vite": "^8.3.0"
+  }
+}