Adds make_feedback_router(repo, product, demo_mode_fn) which returns a
FastAPI APIRouter with GET /status and POST / endpoints. Handles Forgejo
label creation/reuse, issue body assembly (including repro steps for bugs),
demo mode gating, and FORGEJO_API_TOKEN presence checks. 12 tests covering
all status/submit paths, mock Forgejo interaction, and body content assertions.
Also adds fastapi>=0.110 and httpx>=0.27 to [dev] optional deps.
