```

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

exchange-router-fixed.py

@@ -0,0 +1,151 @@
+"""
+Bitcoin Exchange Router for AITBC
+"""
+
+from typing import Dict, Any
+from fastapi import APIRouter, HTTPException, BackgroundTasks
+from sqlmodel import Session
+import uuid
+import time
+import json
+import os
+
+from ..deps import require_admin_key, require_client_key
+from ..domain import Wallet
+from ..schemas import ExchangePaymentRequest, ExchangePaymentResponse
+
+router = APIRouter(tags=["exchange"])
+
+# In-memory storage for demo (use database in production)
+payments: Dict[str, Dict] = {}
+
+# Bitcoin configuration
+BITCOIN_CONFIG = {
+    'testnet': True,
+    'main_address': 'tb1qxy2kgdygjrsqtzq2n0yrf2493p83kkfjhx0wlh',  # Testnet address
+    'exchange_rate': 100000,  # 1 BTC = 100,000 AITBC
+    'min_confirmations': 1,
+    'payment_timeout': 3600  # 1 hour
+}
+
+@router.post("/exchange/create-payment", response_model=ExchangePaymentResponse)
+async def create_payment(
+    request: ExchangePaymentRequest,
+    background_tasks: BackgroundTasks,
+    api_key: str = require_client_key()
+) -> Dict[str, Any]:
+    """Create a new Bitcoin payment request"""
+    
+    # Validate request
+    if request.aitbc_amount <= 0 or request.btc_amount <= 0:
+        raise HTTPException(status_code=400, detail="Invalid amount")
+    
+    # Calculate expected BTC amount
+    expected_btc = request.aitbc_amount / BITCOIN_CONFIG['exchange_rate']
+    
+    # Allow small difference for rounding
+    if abs(request.btc_amount - expected_btc) > 0.00000001:
+        raise HTTPException(status_code=400, detail="Amount mismatch")
+    
+    # Create payment record
+    payment_id = str(uuid.uuid4())
+    payment = {
+        'payment_id': payment_id,
+        'user_id': request.user_id,
+        'aitbc_amount': request.aitbc_amount,
+        'btc_amount': request.btc_amount,
+        'payment_address': BITCOIN_CONFIG['main_address'],
+        'status': 'pending',
+        'created_at': int(time.time()),
+        'expires_at': int(time.time()) + BITCOIN_CONFIG['payment_timeout'],
+        'confirmations': 0,
+        'tx_hash': None
+    }
+    
+    # Store payment
+    payments[payment_id] = payment
+    
+    # Start payment monitoring in background
+    background_tasks.add_task(monitor_payment, payment_id)
+    
+    return payment
+
+@router.get("/exchange/payment-status/{payment_id}")
+async def get_payment_status(payment_id: str) -> Dict[str, Any]:
+    """Get payment status"""
+    
+    if payment_id not in payments:
+        raise HTTPException(status_code=404, detail="Payment not found")
+    
+    payment = payments[payment_id]
+    
+    # Check if expired
+    if payment['status'] == 'pending' and time.time() > payment['expires_at']:
+        payment['status'] = 'expired'
+    
+    return payment
+
+@router.post("/exchange/confirm-payment/{payment_id}")
+async def confirm_payment(
+    payment_id: str,
+    tx_hash: str,
+    api_key: str = require_admin_key()
+) -> Dict[str, Any]:
+    """Confirm payment (webhook from payment processor)"""
+    
+    if payment_id not in payments:
+        raise HTTPException(status_code=404, detail="Payment not found")
+    
+    payment = payments[payment_id]
+    
+    if payment['status'] != 'pending':
+        raise HTTPException(status_code=400, detail="Payment not in pending state")
+    
+    # Verify transaction (in production, verify with blockchain API)
+    # For demo, we'll accept any tx_hash
+    
+    payment['status'] = 'confirmed'
+    payment['tx_hash'] = tx_hash
+    payment['confirmed_at'] = int(time.time())
+    
+    # Mint AITBC tokens to user's wallet
+    try:
+        from ..services.blockchain import mint_tokens
+        await mint_tokens(payment['user_id'], payment['aitbc_amount'])
+    except Exception as e:
+        print(f"Error minting tokens: {e}")
+        # In production, handle this error properly
+    
+    return {
+        'status': 'ok',
+        'payment_id': payment_id,
+        'aitbc_amount': payment['aitbc_amount']
+    }
+
+@router.get("/exchange/rates")
+async def get_exchange_rates() -> Dict[str, float]:
+    """Get current exchange rates"""
+    
+    return {
+        'btc_to_aitbc': BITCOIN_CONFIG['exchange_rate'],
+        'aitbc_to_btc': 1.0 / BITCOIN_CONFIG['exchange_rate'],
+        'fee_percent': 0.5
+    }
+
+async def monitor_payment(payment_id: str):
+    """Monitor payment for confirmation (background task)"""
+    
+    import asyncio
+    
+    while payment_id in payments:
+        payment = payments[payment_id]
+        
+        # Check if expired
+        if payment['status'] == 'pending' and time.time() > payment['expires_at']:
+            payment['status'] = 'expired'
+            break
+        
+        # In production, check blockchain for payment
+        # For demo, we'll wait for manual confirmation
+        
+        await asyncio.sleep(30)  # Check every 30 seconds