## Summary

Adds support for `repository_dispatch` events, enabling backend services to programmatically trigger Claude to perform tasks and receive progress updates via API.

## Architecture

```mermaid
sequenceDiagram
    participant Backend as Backend Service
    participant GH as GitHub
    participant Action as Claude Action
    participant Claude as Claude
    participant MCP as Progress MCP Server
    participant API as Progress API

    Backend->>GH: POST /repos/{owner}/{repo}/dispatches
    Note over Backend,GH: Payload includes:<br/>- description (task)<br/>- progress_endpoint<br/>- correlation_id

    GH->>Action: Trigger workflow<br/>(repository_dispatch)

    Action->>Action: Parse dispatch payload
    Note over Action: Extract task description,<br/>endpoint, correlation_id

    Action->>MCP: Install Progress Server
    Note over MCP: Configure with:<br/>- PROGRESS_ENDPOINT<br/>- CORRELATION_ID<br/>- GITHUB_RUN_ID

    Action->>Claude: Execute task with<br/>MCP tools available

    loop Task Execution
        Claude->>MCP: update_claude_progress()
        MCP->>MCP: Get OIDC token
        MCP->>API: POST progress update
        Note over API: Payload includes:<br/>- correlation_id<br/>- status<br/>- message<br/>- completed_tasks
        API->>Backend: Forward update
    end

    Claude->>Action: Task complete
    Action->>GH: Commit changes
```

## Key Features

### 1. Repository Dispatch Support

- New event handler for `repository_dispatch` events
- Extracts task description, progress endpoint, and correlation ID from `client_payload`
- Bypasses GitHub UI interaction for fully programmatic operation

### 2. Progress Reporting MCP Server

- New MCP server (`progress-server.ts`) for sending progress updates
- OIDC authentication for secure API communication
- Includes correlation ID in all updates for request tracking

### 3. Simplified Dispatch Prompts

- Focused instructions for dispatch events (no PR/issue context)
- Clear directives: answer questions or implement changes
- Automatic progress updates at start and completion

## Implementation Details

### Triggering a Dispatch

```bash
curl -X POST \
  https://api.github.com/repos/{owner}/{repo}/dispatches \
  -H "Authorization: token $GITHUB_TOKEN" \
  -H "Accept: application/vnd.github.v3+json" \
  -d '{
    "event_type": "claude-task",
    "client_payload": {
      "description": "Implement a new feature that...",
      "progress_endpoint": "https://api.example.com/progress",
      "correlation_id": "req-123-abc"
    }
  }'
```

### Progress Update Payload

```json
{
  "repository": "owner/repo",
  "run_id": "123456789",
  "correlation_id": "req-123-abc",
  "status": "in_progress",
  "message": "Implementing feature...",
  "completed_tasks": ["Setup environment", "Created base structure"],
  "current_task": "Writing tests",
  "timestamp": "2024-01-17T12:00:00Z"
}
```

## Security

- **OIDC Authentication**: All progress updates use GitHub OIDC tokens
- **Correlation IDs**: Included in request body (not URL) for security
- **Endpoint Validation**: Progress endpoint must be explicitly provided
- **No Credential Storage**: Tokens are generated per-request

## Testing

To test the repository_dispatch flow:

1. Configure workflow with `repository_dispatch` trigger
2. Send dispatch event with required payload
3. Monitor GitHub Actions logs for execution
4. Verify progress updates at configured endpoint

## Changes

- Added `repository_dispatch` event handling in `context.ts`
- Created new `progress-server.ts` MCP server
- Updated `isDispatch` flag across all event types
- Modified prompt generation for dispatch events
- Made `githubData` optional for dispatch workflows
- Added correlation ID support throughout the pipeline