feat: wire agent.delegate tool with sub-agent configs

- Export createAgentDelegateTool through builtin/index.ts → tools/index.ts
- Register agent.delegate in routing.ts with lazy orchestrator pattern
- Add agent.delegate + agents.list to messaging and coding policy profiles
- Add group:agents tool group to policy.ts
- Add research/code/comms agent config examples to default.yaml
- Add research/code/comms agent configs to user config.yaml
- Add 11 tests for agent-delegate tool (all pass)
- Typecheck clean, no regressions

src/daemon/index.ts

@@ -34,6 +34,57 @@ import type { SkillRegistry, SkillInstaller } from '../skills/index.js';
 import type { GatewayServer } from '../gateway/index.js';
 import { AuditLogger, initAuditLogger } from '../audit/index.js';
 import { BackupScheduler } from '../backup/index.js';
+import {
+  ClaudeCodeBackend,
+  OpenCodeBackend,
+  CodexBackend,
+  GeminiBackend,
+  type ExternalBackend,
+  type ExternalBackendName,
+} from '../backends/index.js';
+
+function createConfiguredExternalBackends(config: Config): {
+  backends: Partial<Record<ExternalBackendName, ExternalBackend>>;
+  defaultName?: ExternalBackendName;
+} {
+  const backends: Partial<Record<ExternalBackendName, ExternalBackend>> = {};
+
+  if (config.backends.claude_code.enabled) {
+    backends.claude_code = new ClaudeCodeBackend(
+      config.backends.claude_code.path,
+      config.backends.claude_code.args,
+      config.backends.claude_code.timeout_ms,
+    );
+  }
+  if (config.backends.opencode.enabled) {
+    backends.opencode = new OpenCodeBackend(
+      config.backends.opencode.path,
+      config.backends.opencode.args,
+      config.backends.opencode.timeout_ms,
+    );
+  }
+  if (config.backends.codex.enabled) {
+    backends.codex = new CodexBackend(
+      config.backends.codex.path,
+      config.backends.codex.args,
+      config.backends.codex.timeout_ms,
+    );
+  }
+  if (config.backends.gemini.enabled) {
+    backends.gemini = new GeminiBackend(
+      config.backends.gemini.path,
+      config.backends.gemini.args,
+      config.backends.gemini.timeout_ms,
+    );
+  }
+
+  const selectedDefault = config.backends.default;
+  const defaultName = selectedDefault && backends[selectedDefault]
+    ? selectedDefault
+    : (Object.keys(backends)[0] as ExternalBackendName | undefined);
+
+  return { backends, defaultName };
+}
 
 export interface DaemonContext {
   config: Config;
@@ -163,6 +214,7 @@ export async function startDaemon(config: Config, options?: StartDaemonOptions):
   const messageRouter = createMessageRouter({
     sessionManager, modelRouter, systemPrompt, toolRegistry, toolExecutor,
     config, memoryStore, agentConfigRegistry, agentRouter, sandboxManager, commandRegistry, intentRegistry, routingPolicy, skillRegistry,
+    ...createConfiguredExternalBackends(config),
   });
   channelRegistry.setMessageHandler(messageRouter.handler);
   channelAgents = messageRouter.agents;