feat: Scheduled Jobs Service

Features:
- Cron scheduling (standard syntax)
- HTTP triggers (GET/POST)
- Timezone support
- Retry logic with configurable attempts
- Execution logs with response data
- Manual trigger (run now)
- Stats: runs, successes, failures, avg duration
- Beautiful dashboard UI

Demo: 5 jobs (health, cleanup, metrics, backup, report)

Live: https://blackroad-cron.amundsonalexa.workers.dev

package.json

@@ -0,0 +1,17 @@
+{
+  "name": "@blackroad/cron",
+  "version": "1.0.0",
+  "description": "Scheduled Jobs Service",
+  "main": "src/index.ts",
+  "scripts": {
+    "dev": "wrangler dev",
+    "deploy": "wrangler deploy"
+  },
+  "author": "BlackRoad OS, Inc.",
+  "license": "MIT",
+  "devDependencies": {
+    "@cloudflare/workers-types": "^4.20240117.0",
+    "typescript": "^5.3.0",
+    "wrangler": "^3.0.0"
+  }
+}