fastapi-testlisted

Write tests for the current changes. Follow these steps: 1. **Read CLAUDE.md** to understand the project's test framework, conventions, and test commands. 2. **Read any `.claude/rules/*.md`** whose `paths:` glob matches the changed files — they capture testing conventions specific to this layer (e.g. how API tests are structured vs. how DB tests are structured). 3. **Identify what changed** with `git diff master...HEAD` (the whole branch's work), plus `git diff` and `git diff --cached` for any uncommitted edits — not a bare `git diff`, which would miss everything already committed on the branch. Classify the change: - **Pure refactor** (code moved/renamed, no behavior change): update existing tests' imports and call sites; do NOT invent new tests for behavior that already had coverage. - **New behavior or modified behavior**: continue to step 4. 4. **Find existing test files** for the modules you're testing. Read them fully — match their patterns: - File naming and location conventions. - Fixtures, factories, helpers, and setup/teardown patterns. - Assertion style and test structure. - How similar features are tested (use as a template). 5. **Write focused tests** that cover: - **Happy path** — the expected behavior works correctly. - **Edge cases** — empty inputs, boundary values, null/nil, large inputs. - **Error cases** — invalid input, missing data, permission failures. Test that errors are handled, not just that they don't crash. - **Behavi