Implement central configuration, custom exceptions, logging utilities, Pydantic models, and Redis client for BitByLaw integration

- Added `config.py` for centralized configuration management including Sync, API, Advoware, EspoCRM, Redis, Logging, Calendar Sync, and Feature Flags.
- Created `exceptions.py` with a hierarchy of custom exceptions for integration errors, API errors, sync errors, and Redis errors.
- Developed `logging_utils.py` for a unified logging wrapper supporting structured logging and performance tracking.
- Defined Pydantic models in `models.py` for data validation of Advoware and EspoCRM entities, including sync operation models.
- Introduced `redis_client.py` for a centralized Redis client factory with connection pooling, automatic reconnection, and health checks.

steps/vmh/beteiligte_sync_event_step.py

@@ -17,9 +17,16 @@ from services.advoware_service import AdvowareService
 from services.espocrm import EspoCRMAPI
 from services.espocrm_mapper import BeteiligteMapper
 from services.beteiligte_sync_utils import BeteiligteSync
+from services.redis_client import get_redis_client
+from services.exceptions import (
+    AdvowareAPIError,
+    EspoCRMAPIError,
+    SyncError,
+    RetryableError,
+    is_retryable
+)
+from services.logging_utils import get_step_logger
 import json
-import redis
-import os
 
 config = {
     "name": "VMH Beteiligte Sync Handler",
@@ -35,32 +42,36 @@ config = {
 }
 
 
-async def handler(event_data: Dict[str, Any], ctx: FlowContext[Any]):
-    """Zentraler Sync-Handler für Beteiligte"""
+async def handler(event_data: Dict[str, Any], ctx: FlowContext[Any]) -> Optional[Dict[str, Any]]:
+    """
+    Zentraler Sync-Handler für Beteiligte
+    
+    Args:
+        event_data: Event data mit entity_id, action, source
+        ctx: Motia FlowContext
+        
+    Returns:
+        Optional result dict
+    """
     entity_id = event_data.get('entity_id')
     action = event_data.get('action')
     source = event_data.get('source')
     
+    step_logger = get_step_logger('beteiligte_sync', ctx)
+    
     if not entity_id:
-        ctx.logger.error("Keine entity_id im Event gefunden")
-        return
+        step_logger.error("Keine entity_id im Event gefunden")
+        return None
     
-    ctx.logger.info(f"🔄 Sync-Handler gestartet: {action.upper()} | Entity: {entity_id} | Source: {source}")
-    
-    # Shared Redis client for distributed locking
-    redis_host = os.getenv('REDIS_HOST', 'localhost')
-    redis_port = int(os.getenv('REDIS_PORT', '6379'))
-    redis_db = int(os.getenv('REDIS_DB_ADVOWARE_CACHE', '1'))
-    
-    redis_client = redis.Redis(
-        host=redis_host,
-        port=redis_port,
-        db=redis_db,
-        decode_responses=True
+    step_logger.info(
+        f"🔄 Sync-Handler gestartet: {action.upper()} | Entity: {entity_id} | Source: {source}"
     )
     
+    # Get shared Redis client (centralized)
+    redis_client = get_redis_client(strict=False)
+    
     # APIs initialisieren
-    espocrm = EspoCRMAPI()
+    espocrm = EspoCRMAPI(ctx)
     advoware = AdvowareAPI(ctx)
     sync_utils = BeteiligteSync(espocrm, redis_client, ctx)
     mapper = BeteiligteMapper()