Enhance environment configuration and API documentation for Milestone 11

Implement Milestone 8 by adding new endpoints for URL ingestion and collection management. Introduce `httpx` as a dependency for handling URL downloads, and enhance the API with endpoints for listing and deleting collections. Update request and response models to support new functionalities, and refactor existing routes for improved clarity and organization.

Implement Milestone 7 by introducing background ingestion jobs. Update environment configuration to include job database path, enhance job tracking with new endpoints, and refactor ingestion logic to support asynchronous processing. Modify response models to include job details and ensure proper initialization of the jobs database on startup.

Implement Milestone 3 by adding configuration and request/response contracts. Introduce new models for requests and responses, enhance route handlers with schema validation, and update dependencies to include pydantic-settings. Update audit, ingest, jobs, and query routes to utilize new models and improve response structures.