Fix: correct db access

[S1ro1]

Fixes api issues.

[Copilot]

Pull Request Overview

Fixes API issues by correcting the database access patterns.

• Removed the context manager decorator from get_db and now return the database directly.
• Updated the prepare_submission call to pass the entire backend instead of just backend.db.

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
src/discord-cluster-manager/api/main.py	Removed contextmanager usage in get_db and adjusted exception format.
src/discord-cluster-manager/api/api_utils.py	Changed prepare_submission parameter from backend.db to backend.

Comments suppressed due to low confidence (2)

src/discord-cluster-manager/api/main.py:73

• The get_db function no longer functions as a context manager; please update its docstring to reflect that it now directly returns the database instance.

    return backend_instance.db

src/discord-cluster-manager/api/api_utils.py:142

• Ensure that prepare_submission is updated accordingly to handle the full backend object instead of just the database property, as this change modifies the expected parameter type.

        req = prepare_submission(submission, backend)

[ngc92]

lgtm