feat(gateway): Phase 4 - Save & List Connector Configs

[TelivANT]

Phase 4 Implementation - 100% Complete! 🎉

Features

• ✅ Save connector configurations
• ✅ List saved configurations
• ✅ File-based storage (minimal dependencies)
• ✅ UUID v7 for config IDs

New Endpoints

1. POST /v1/wiki/connectors - Save configuration
2. GET /v1/wiki/connectors/saved - List saved configs

Storage Design

• Path: ./data/connectors/{id}.json
• Format: JSON (human-readable)
• No encryption: Can add AES-256-GCM later if needed
• Async I/O: tokio::fs for non-blocking operations

Request/Response Examples

Save Config:

POST /v1/wiki/connectors
{
  "name": "My GitHub Repo",
  "connector_type": "git",
  "config": {
    "url": "https://github.com/user/repo.git",
    "token": "ghp_xxx"
  }
}

Response:
{
  "id": "<uuid-v7>",
  "message": "Connector saved successfully"
}

List Configs:

GET /v1/wiki/connectors/saved

Response:
[
  {
    "id": "<uuid>",
    "name": "My GitHub Repo",
    "connector_type": "git",
    "config": {...},
    "created_at": "2026-02-21T15:30:00Z"
  }
]

Complete API (7/7 Endpoints) ✅

1. ✅ GET /v1/wiki/connectors - List connector types
2. ✅ POST /v1/wiki/connectors/test - Test connection
3. ✅ POST /v1/wiki/connectors/browse - Browse directories
4. ✅ POST /v1/wiki/connectors/generate - Generate wiki
5. ✅ GET /v1/wiki/jobs/{id} - Check status
6. ✅ POST /v1/wiki/connectors - Save config
7. ✅ GET /v1/wiki/connectors/saved - List configs

Implementation Details

• No external DB: Uses file system (project standard)
• Minimal code: ~80 lines for both endpoints
• Type-safe: Rust structs with serde
• Async: Non-blocking I/O

Future Enhancements (Optional)

• Add AES-256-GCM encryption for sensitive fields
• Add user_id filtering
• Add config update/delete endpoints
• Migrate to Redis/SQLite if needed

Progress Summary

• ✅ Phase 1: Core API (3 endpoints)
• ✅ Phase 2: Session management
• ✅ Phase 3: Wiki generation
• ✅ Phase 4: Config persistence

Total: 8 connectors + 7 API endpoints + ~2400 lines of code

Closes #34 follow-up