Refactor settings system and improve context initialization

Backend:
- Add type validation and coercion for settings API
- Implement SettingStorage and SettingType in registry
- Improve CRUD operations for settings

Frontend:
- Refactor Theme, Language, Sidebar, ViewMode contexts
- Simplify admin components (GeneralTab, SettingsTab, UsersTab)
- Add new settings endpoints to API client
- Improve App initialization flow

Infrastructure:
- Update Dockerfile and docker-compose.yml
- Add .dockerignore
- Update Makefile and README

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

backend/app/crud/base.py

@@ -71,7 +71,7 @@ class CRUDBase(Generic[ModelType, CreateSchemaType, UpdateSchemaType]):
 
     def delete(self, db: Session, *, id: Any) -> ModelType:
         """Delete a record."""
-        obj = db.query(self.model).get(id)
+        obj = db.get(self.model, id)
         db.delete(obj)
         db.commit()
         return obj

backend/app/crud/settings.py

@@ -1,5 +1,6 @@
 """CRUD operations for Settings."""
 
+import json
 from typing import Optional
 from sqlalchemy.orm import Session
 
@@ -27,13 +28,16 @@ def update_setting(db: Session, key: str, value: any) -> Settings:
         setting = Settings(key=key)
         db.add(setting)
     
-    # Determine if value is bool or string
+    # Determine how to store the value (DB has only bool + string columns)
     if isinstance(value, bool):
         setting.value_bool = value
         setting.value_str = None
-    elif isinstance(value, str) and value.lower() in ('true', 'false'):
-        setting.value_bool = value.lower() == 'true'
+    elif isinstance(value, str) and value.lower() in ("true", "false", "1", "0"):
+        setting.value_bool = value.lower() in ("true", "1")
         setting.value_str = None
+    elif isinstance(value, (dict, list)):
+        setting.value_str = json.dumps(value)
+        setting.value_bool = None
     else:
         setting.value_str = str(value)
         setting.value_bool = None