```

chore: refactor logging module, update genesis timestamp, remove model relationships, and reorganize routers

- Rename logging.py to logger.py and update import paths in poa.py and main.py
- Update devnet genesis timestamp to 1766828620
- Remove SQLModel Relationship declarations from Block, Transaction, and Receipt models
- Add SessionDep type alias and get_session dependency in coordinator-api deps
- Reorganize coordinator-api routers: replace explorer/registry with exchange, users, marketplace

docs/developer/api/coordinator/overview.md

@@ -0,0 +1,140 @@
+---
+title: Coordinator API Overview
+description: Introduction to the AITBC Coordinator API
+---
+
+# Coordinator API Overview
+
+The Coordinator API is the central service of the AITBC platform, responsible for job management, marketplace operations, and coordination between various components.
+
+## Base URL
+
+```
+Production: https://aitbc.bubuit.net/api
+Staging: https://staging-api.aitbc.io
+Development: http://localhost:8011
+```
+
+## Authentication
+
+All API endpoints require authentication using an API key. Include the API key in the request header:
+
+```http
+X-API-Key: your_api_key_here
+```
+
+Get your API key from the [AITBC Dashboard](https://dashboard.aitbc.io).
+
+## Core Concepts
+
+### Jobs
+Jobs are the primary unit of work in AITBC. They represent AI computations that need to be executed.
+
+```json
+{
+  "job_id": "job_1234567890",
+  "type": "ai-inference",
+  "status": "running",
+  "created_at": "2024-01-01T12:00:00Z",
+  "estimated_completion": "2024-01-01T12:05:00Z"
+}
+```
+
+### Marketplace
+The marketplace connects job creators with miners who can execute the jobs.
+
+```json
+{
+  "offer_id": "offer_1234567890",
+  "job_type": "image-classification",
+  "price": "0.001",
+  "miner_id": "miner_1234567890"
+}
+```
+
+### Receipts
+Receipts provide cryptographic proof of job execution and results.
+
+```json
+{
+  "receipt_id": "receipt_1234567890",
+  "job_id": "job_1234567890",
+  "signature": {
+    "sig": "base64_signature",
+    "public_key": "base64_public_key"
+  }
+}
+```
+
+## Rate Limits
+
+API requests are rate-limited to ensure fair usage:
+
+| Plan | Requests per minute | Burst |
+|------|---------------------|-------|
+| Free | 60 | 10 |
+| Pro | 600 | 100 |
+| Enterprise | 6000 | 1000 |
+
+## Error Handling
+
+The API uses standard HTTP status codes and returns detailed error messages:
+
+```json
+{
+  "error": {
+    "code": "INVALID_API_KEY",
+    "message": "The provided API key is invalid",
+    "details": {
+      "request_id": "req_1234567890"
+    }
+  }
+}
+```
+
+Common error codes:
+- `400 Bad Request` - Invalid request parameters
+- `401 Unauthorized` - Invalid or missing API key
+- `403 Forbidden` - Insufficient permissions
+- `404 Not Found` - Resource not found
+- `429 Too Many Requests` - Rate limit exceeded
+- `500 Internal Server Error` - Server error
+
+## SDK Support
+
+Official SDKs are available for:
+- [Python](../../developer-guide/sdks/python.md)
+- [JavaScript/TypeScript](../../developer-guide/sdks/javascript.md)
+
+## WebSocket API
+
+Real-time updates are available through WebSocket connections:
+
+```javascript
+const ws = new WebSocket('wss://aitbc.bubuit.net/ws');
+
+ws.onmessage = (event) => {
+  const data = JSON.parse(event.data);
+  console.log('Job update:', data);
+};
+```
+
+## OpenAPI Specification
+
+The complete OpenAPI 3.0 specification is available:
+- [View in Swagger UI](https://aitbc.bubuit.net/api/docs)
+- [Download JSON](openapi.md)
+
+## Getting Started
+
+1. [Get an API key](https://dashboard.aitbc.io/api-keys)
+2. [Review authentication](authentication.md)
+3. [Explore endpoints](endpoints.md)
+4. [Check examples](../../developer-guide/examples.md)
+
+## Support
+
+- 📖 [Documentation](../../)
+- 💬 [Discord](https://discord.gg/aitbc)
+- 🐛 [Report Issues](https://github.com/aitbc/issues)
+- 📧 [api-support@aitbc.io](mailto:api-support@aitbc.io)