feat(security): grow Yerin's toolset (pending_review, resource_exposure, token_audit)

Three more read-only tools on securityRegistry:
- pending_review: agent-proposed changes awaiting approval (injection surface)
- resource_exposure: host/url/status attack-surface inventory (resources.listExposure,
  scalar cols only — no monitoring/metadata/credentials)
- token_audit: token label/last_used/revoked, never the hash

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

lib/ai/agent/tools/security/index.js

@@ -1,6 +1,9 @@
 import { createRegistry } from '../../registry.js';
 import { auditLogTool } from './audit_log.js';
 import { agentInventoryTool } from './agent_inventory.js';
+import { pendingReviewTool } from './pending_review.js';
+import { resourceExposureTool } from './resource_exposure.js';
+import { tokenAuditTool } from './token_audit.js';
 
 // Yerin's security toolset — read-only observability, kept in its own registry
 // so the security agent gets security tools (not Dross's propose_change). A
@@ -9,3 +12,6 @@ import { agentInventoryTool } from './agent_inventory.js';
 export const securityRegistry = createRegistry();
 securityRegistry.registerTool(auditLogTool);
 securityRegistry.registerTool(agentInventoryTool);
+securityRegistry.registerTool(pendingReviewTool);
+securityRegistry.registerTool(resourceExposureTool);
+securityRegistry.registerTool(tokenAuditTool);