Add CI check to ensure uv.lock is in sync with pyproject.toml

[dadofsambonzuki]

Problem

The uv.lock file can become out of sync with pyproject.toml when dependencies are added or updated. This caused a production deployment failure where flask-login and other dependencies were listed in pyproject.toml but missing from uv.lock.

Proposed Solution

Add a CI workflow that checks if uv.lock is in sync with pyproject.toml on every PR.

Implementation Options

Option 1: Use uv lock --check (preferred)

If supported by uv version:

Option 2: Check for changes after uv lock

Workflow Location

Example Workflow

Acceptance Criteria

• CI workflow runs on all PRs
• Fails if uv.lock is out of sync with pyproject.toml
• Provides clear error message about how to fix (run uv lock)

References

• PR Fix Railway deployment: auto-create flask_session directory #41 where this issue was discovered
• Astral uv documentation