Add built-in scheduler with group-scoped tasks

- Custom nanoclaw MCP server with scheduling tools (schedule_task,
  list_tasks, get_task, update_task, pause/resume/cancel_task, send_message)
- Tasks run as full agents in their group's context
- Support for cron, interval, and one-time schedules
- Task run logging with duration and results
- Main channel has Bash access for admin tasks (query DB, manage groups)
- Other groups restricted to file operations only
- Updated docs and requirements

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

package.json

@@ -16,9 +16,11 @@
     "@anthropic-ai/claude-agent-sdk": "^0.1.0",
     "@whiskeysockets/baileys": "^7.0.0-rc.9",
     "better-sqlite3": "^11.8.1",
+    "cron-parser": "^5.5.0",
     "pino": "^9.6.0",
     "pino-pretty": "^13.0.0",
-    "qrcode-terminal": "^0.12.0"
+    "qrcode-terminal": "^0.12.0",
+    "zod": "^4.3.6"
   },
   "devDependencies": {
     "@types/better-sqlite3": "^7.6.12",