feat: implement work heartbeat service for health checks and task dispatching

- Introduced a new heartbeat service that runs at defined intervals to perform health checks on workers and fill available task slots based on priority.
- Added a health tool to scan worker health across projects with optional auto-fix capabilities.
- Updated the status tool to provide a lightweight overview of worker states and queue counts without health checks.
- Enhanced task creation tool descriptions to clarify task state handling.
- Implemented tests for the work heartbeat logic, ensuring proper project resolution, worker state management, and task prioritization.

lib/setup/config.ts

@@ -6,6 +6,7 @@
 import fs from "node:fs/promises";
 import path from "node:path";
 import type { Tier } from "../tiers.js";
+import { HEARTBEAT_DEFAULTS } from "../services/heartbeat.js";
 
 function openclawConfigPath(): string {
   return path.join(process.env.HOME ?? "/home/lauren", ".openclaw", "openclaw.json");
@@ -35,6 +36,7 @@ export async function writePluginConfig(
     config.plugins.entries.devclaw.config.projectExecution = projectExecution;
   }
 
+  ensureHeartbeatDefaults(config);
   configureSubagentCleanup(config);
 
   if (agentId) {
@@ -86,3 +88,10 @@ function addToolRestrictions(config: Record<string, unknown>, agentId: string):
     delete agent.tools.allow;
   }
 }
+
+function ensureHeartbeatDefaults(config: Record<string, unknown>): void {
+  const devclaw = (config as any).plugins.entries.devclaw.config;
+  if (!devclaw.work_heartbeat) {
+    devclaw.work_heartbeat = { ...HEARTBEAT_DEFAULTS };
+  }
+}