[BUG] No Real Database Connectivity

[Limeload]

The application currently relies on mock data and external MCP servers. No direct database connectivity exists.

Missing Components:

• SQLAlchemy integration for PostgreSQL/MySQL
• Snowflake connector implementation
• SQLite support
• Connection pooling per user
• Query execution engine

Expected Implementation:

# server/database/connectors.py
class DatabaseConnector:
    def __init__(self, credential: DatabaseCredential):
        self.credential = credential
        self.engine = self._create_engine()
    
    def execute_query(self, query: str) -> QueryResult:
        # Implement actual query execution
        pass
    
    def get_schema(self) -> SchemaMetadata:
        # Implement schema introspection
        pass

Acceptance Criteria:

• Direct database connectivity
• Support for PostgreSQL, MySQL, Snowflake, SQLite
• Connection pooling and management
• Query execution with proper error handling
• Schema introspection capabilities

[github-actions]

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