Add Next.js web app

Feed with live updates and pinning, profiles with follow/pin, featured song
picker, settings for all music services, and account deletion.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01MzFywujuH9TiuXbr9vjoX8

apps/web/package.json

@@ -0,0 +1,24 @@
+{
+  "name": "@musicshare/web",
+  "version": "0.0.0",
+  "private": true,
+  "type": "module",
+  "scripts": {
+    "dev": "next dev --port 3737",
+    "build": "next build",
+    "start": "next start --port 3737",
+    "typecheck": "tsc -p ."
+  },
+  "devDependencies": {
+    "@types/react": "~19.2.2",
+    "@types/react-dom": "~19.2.2",
+    "typescript": "~6.0.3"
+  },
+  "dependencies": {
+    "next": "^16.3.8",
+    "react": "19.2.3",
+    "react-dom": "19.2.3",
+    "swr": "^2.5.1",
+    "@musicshare/shared": "*"
+  }
+}