Refactor payment service, fix DB session, and consolidate endpoints

- Fix critical NameError in database.py by restoring Session factory
- Refactor payment_service.py and crud.py to use shared constants.py and utils.py
- Deduplicate state mapping and input sanitization logic
- Move transaction amount calculation logic from CRUD to Router layer
- Enforce type safety in schemas using IntEnum for TransactionType/Status
- Move capture endpoint from transaction.py to payment.py (now /payments/capture)
- Update create_customer_profile signature for clarity

app/schemas.py

@@ -4,7 +4,9 @@ from pydantic import BaseModel, ConfigDict, Field, field_validator
 from typing import List, Optional
 from datetime import datetime
 from decimal import Decimal
+from decimal import Decimal
 import re
+from .constants import TransactionType, TransactionStatus
 
 # --- NEW SCHEMAS FOR CIM WORKFLOW (Now with correct Pydantic V2 config) ---
 
@@ -68,7 +70,7 @@ class TransactionAuthorizeByCardID(BaseModel):
 class TransactionBase(BaseModel):
     preauthorize_amount: Optional[Decimal] = None
     charge_amount: Optional[Decimal] = None
-    transaction_type: int
+    transaction_type: TransactionType
     service_id: Optional[int] = None
     delivery_id: Optional[int] = None
     auto_id: Optional[int] = None
@@ -94,8 +96,8 @@ class TransactionCapture(BaseModel):
 
 class Transaction(TransactionBase):
     id: int
-    transaction_type: int
-    status: int
+    transaction_type: TransactionType
+    status: TransactionStatus
     auth_net_transaction_id: Optional[str] = None
     customer_id: int
     created_at: datetime