Refactor config system to use Pydantic validation

Refactored configuration classes to inherit from a new ValidatedConfigBase using Pydantic for robust validation and error reporting. Updated api_ada_configs.py, config.py, config_base.py, and official_configs.py to replace dataclasses with Pydantic models, add field validation, and improve error messages. This change enhances configuration reliability and developer feedback for misconfigurations. Also includes minor code cleanups and removal of unused variables in other modules.

src/chat/emoji_system/emoji_manager.py

@@ -906,7 +906,6 @@ class EmojiManager:
                 with get_db_session() as session:
                 # from src.common.database.database_model_compat import Images
 
-                    stmt = select(Images).where((Images.emoji_hash == image_hash) & (Images.type == "emoji"))
                     existing_image = session.query(Images).filter((Images.emoji_hash == image_hash) & (Images.type == "emoji")).one_or_none()
                     if existing_image and existing_image.description:
                         existing_description = existing_image.description