## Implementation Plan: Fix Incorrect Content-Length Headers via GZipMiddleware

### Change

Modify `pyproject.toml` to pin minimum versions for `starlette` and `fastapi` to releases that include the GZipMiddleware `Content-Length` fix.

**File:** `pyproject.toml`  
**Section:** `[project.dependencies]` (or similar, where `fastapi` and `starlette` are listed)  
**Action:** Replace the bare dependency lines with version-constrained ones:

```
fastapi>=0.110.0
starlette>=0.37.0
```

If either package appears in multiple dependency groups (e.g., `[project.optional-dependencies]`), apply the same constraint everywhere.

### Verification Steps (Definition of Done)

1. **Apply the change** – edit `pyproject.toml` to add the minimum version constraints as described.
2. **Install updated dependencies** – run:
   ```bash
   PIP_REQUIRE_VIRTUALENV=false pip install -e '.[dev]' -q
   ```
   (The environment variable bypasses the PEP 668 restriction that caused previous failures.)
3. **Run the test command** – execute:
   ```bash
   make test-unit
   ```
   All tests pass with exit code 0.
4. **Run the lint command** – execute:
   ```bash
   pip install -q ruff && ruff check .
   ```
   Ruff exits with code 0 (no linting errors).
5. **Confirm installed versions** – (optional but recommended) run:
   ```bash
   pip show starlette fastapi | grep -E "^Version:"
   ```
   Verify `starlette >= 0.37.0` and `fastapi >= 0.110.0`.

All steps must succeed without any failures or errors beyond warnings unrelated to code correctness.