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/tsconfig.json

@@ -0,0 +1,13 @@
+{
+  "extends": "../../tsconfig.base.json",
+  "compilerOptions": {
+    "lib": ["DOM", "DOM.Iterable", "ES2023"],
+    "jsx": "preserve",
+    "allowJs": false,
+    "incremental": true,
+    "plugins": [{ "name": "next" }],
+    "paths": { "@/*": ["./src/*"] }
+  },
+  "include": ["next-env.d.ts", "src", ".next/types/**/*.ts"],
+  "exclude": ["node_modules"]
+}