Build hn-reader: keyboard-driven Hacker News reader

Vite/React + shadcn/ui frontend with Superhuman-style keyboard nav
(j/k/o/v/e/s/u, feed switching, localStorage caching for instant
loads) backed by an Express API that polls the HN Firebase API into
Postgres and serves cached feeds/comments. Instrumented with
OpenTelemetry (traces/metrics/logs via OTLP/HTTP).

tsconfig.app.json

@@ -0,0 +1,30 @@
+{
+  "compilerOptions": {
+    "tsBuildInfoFile": "./node_modules/.tmp/tsconfig.app.tsbuildinfo",
+    "target": "es2023",
+    "lib": ["ES2023", "DOM"],
+    "module": "esnext",
+    "types": ["vite/client"],
+    "allowArbitraryExtensions": true,
+    "skipLibCheck": true,
+
+    /* Bundler mode */
+    "moduleResolution": "bundler",
+    "allowImportingTsExtensions": true,
+    "verbatimModuleSyntax": true,
+    "moduleDetection": "force",
+    "noEmit": true,
+    "jsx": "react-jsx",
+
+    /* Linting */
+    "noUnusedLocals": true,
+    "noUnusedParameters": true,
+    "erasableSyntaxOnly": true,
+    "noFallthroughCasesInSwitch": true,
+
+    "paths": {
+      "@/*": ["./src/*"]
+    }
+  },
+  "include": ["src"]
+}