feat: add GitHub repository dashboard with Prometheus metrics

ghtracker authenticates as a GitHub App and scans a configured list of repositories on a schedule. It serves a dashboard, a JSON state endpoint, a health probe and Prometheus metrics.

The dashboard lists only items that need attention: failing workflows, pull requests that wait too long or fail their checks, stale issues and projects that failed to scan. It has search, dynamic filters and a button that rescans on demand. The Vue app is embedded in the Go binary.

The client protects the GitHub rate limit with conditional requests, a request reserve and Retry-After handling.

tsconfig.json

@@ -0,0 +1,20 @@
+{
+  "compilerOptions": {
+    "target": "ES2022",
+    "module": "ESNext",
+    "moduleResolution": "bundler",
+    "lib": ["ES2022", "DOM", "DOM.Iterable"],
+    "strict": true,
+    "noUnusedLocals": true,
+    "noUnusedParameters": true,
+    "noEmit": true,
+    "skipLibCheck": true,
+    "isolatedModules": true,
+    "verbatimModuleSyntax": true,
+    "jsx": "preserve",
+    "types": ["vite/client", "node"],
+    "baseUrl": ".",
+    "paths": { "@/*": ["src/*"] }
+  },
+  "include": ["src/**/*.ts", "src/**/*.vue", "vite.config.ts"]
+}