refactor: add low-effort improvements to AITBC core system flows

- Add detailed inline comments to transaction signing logic in crypto.py
- Standardize error messages in agent lifecycle functions in events.py
- Replace print statements with proper logging in event bus
- Add logging statements to configuration loading flow in config.py
- Improve error message consistency across event handlers

aitbc/config.py

@@ -42,6 +42,14 @@ class BaseAITBCConfig(BaseSettings):
         description="Log format string"
     )
     
+    def __init__(self, **kwargs):
+        """Initialize configuration with logging"""
+        super().__init__(**kwargs)
+        logger.info(f"Loading configuration for {self.app_name} v{self.app_version} in {self.environment} environment")
+        logger.debug(f"Data directory: {self.data_dir}")
+        logger.debug(f"Config directory: {self.config_dir}")
+        logger.debug(f"Log directory: {self.log_dir}")
+
 
 class AITBCConfig(BaseAITBCConfig):
     """

aitbc/crypto.py

@@ -100,12 +100,15 @@ def encrypt_private_key(private_key: str, password: str) -> str:
 def decrypt_private_key(encrypted_key: str, password: str) -> str:
     """Decrypt private key using Fernet symmetric encryption"""
     try:
-        # Decode combined data
+        # Decode combined salt + encrypted data
         combined = base64.urlsafe_b64decode(encrypted_key.encode('utf-8'))
+        
+        # Extract salt (first 16 bytes) and encrypted data (remaining bytes)
         salt = combined[:16]
         encrypted_data = combined[16:]
         
-        # Derive key from password
+        # Derive same encryption key from password using stored salt
+        # Must use identical parameters as encryption for successful decryption
         password_bytes = password.encode('utf-8')
         kdf = PBKDF2HMAC(
             algorithm=hashes.SHA256(),
@@ -115,7 +118,7 @@ def decrypt_private_key(encrypted_key: str, password: str) -> str:
         )
         key = base64.urlsafe_b64encode(kdf.derive(password_bytes))
         
-        # Decrypt private key
+        # Decrypt private key using derived key
         fernet = Fernet(key)
         decrypted_key = fernet.decrypt(encrypted_data)
         return decrypted_key.decode('utf-8')

aitbc/events.py

@@ -261,7 +261,9 @@ class EventRouter:
                         await handler(event)
                     else:
                         handler(event)
+                    self.logger.debug(f"Routed event {event.event_type} to handler")
                     return True
                 except Exception as e:
-                    print(f"Error in routed handler: {e}")
+                    self.logger.error(f"Routed handler failed for {event.event_type}: {e}")
+        self.logger.debug(f"No matching route found for event {event.event_type}")
         return False