feat(explorer): complete Coordinator integration

[prosdev]

🎯 Overview

Completes the Explorer Subagent implementation by adding full Coordinator integration, closing out all acceptance criteria for Issue #9.

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✅ Acceptance Criteria (Issue #9)

All criteria now met:

• ✅ Explorer can identify patterns in code (pattern action)
• ✅ Code exploration works across repositories (semantic search via indexer)
• ✅ Relationship mapping implemented (relationships action)
• ✅ Similar code identification works (similar action, fixed in PR fix(explore): search file content instead of filename for similar code #21)
• ✅ Integrates with Subagent Coordinator (THIS PR)

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📦 What's New

1. Coordinator Integration Tests (17 tests, 100% passing)

pnpm test packages/subagents/src/coordinator/coordinator.integration.test.ts

Coverage:

• ✅ Agent registration and initialization
• ✅ Message routing (all 4 Explorer actions)
• ✅ Task execution via task queue
• ✅ Health checks and monitoring
• ✅ Context sharing (indexer access)
• ✅ Error handling (unknown agents, invalid actions)
• ✅ Graceful shutdown

2. Enhanced Documentation

• Complete integration guide with step-by-step setup
• Task-based exploration patterns
• Multi-agent coordination examples
• Health monitoring and statistics
• Graceful shutdown handling

3. Type Exports

All Explorer types now exported from main package for proper typing:

import type { 
  ExplorationRequest,
  PatternSearchRequest,
  SimilarCodeRequest,
  RelationshipRequest,
  InsightsRequest,
} from '@lytics/dev-agent-subagents';

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🧪 Testing

All tests passing:

✓ packages/subagents/src/coordinator/coordinator.integration.test.ts (17 tests)

Test Files  1 passed (1)
     Tests  17 passed (17)

Test Highlights:

• Explorer registers successfully with Coordinator
• All message types route correctly
• Tasks execute via queue with proper lifecycle
• Health checks reflect indexer state
• Context (indexer) shared between components

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💻 Usage Example

import { 
  SubagentCoordinator, 
  ExplorerAgent,
  type ExplorationRequest 
} from '@lytics/dev-agent-subagents';
import { RepositoryIndexer } from '@lytics/dev-agent-core';

// Setup indexer and coordinator
const indexer = new RepositoryIndexer({ repositoryPath: './' });
await indexer.initialize();

const coordinator = new SubagentCoordinator();
coordinator.getContextManager().setIndexer(indexer);

// Register Explorer
const explorer = new ExplorerAgent();
await coordinator.registerAgent(explorer);

coordinator.start();

// Properly typed exploration request
const request: ExplorationRequest = {
  action: 'pattern',
  query: 'authentication logic',
  limit: 10,
  threshold: 0.7,
};

const response = await coordinator.sendMessage({
  type: 'request',
  sender: 'app',
  recipient: 'explorer',
  payload: request,
});

console.log(response?.payload);

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📊 Stats

• 3 atomic commits (focused, testable)
• +516 lines, -13 lines (tests + docs + types)
• 17 new integration tests (100% passing)
• 13 new type exports (full type safety)
• 0 linting/type errors

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🔗 Related

Closes #9

Note: PR #18 incorrectly closed #11 (Configuration Management). Issue #11 should be reopened as configuration management is not yet implemented.

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✅ Checklist

• Integration tests added and passing
• Documentation updated with full examples
• Type exports for external consumers
• All existing tests still pass
• No linting or type errors
• Atomic commits with clear messages
• Issue Implement Explorer Subagent #9 acceptance criteria fully met