fastapi-knowledge-patch

# FastAPI Knowledge Patch Baseline: FastAPI through 0.115.12 with established Pydantic v2 integration, dependency injection, endpoints, OpenAPI, middleware, security, CORS, background tasks, WebSockets, and lifespan events; covered range: included changes through the `2026-07` batch. Use this patch before changing a FastAPI application or its Pydantic, SQLModel, Starlette, or Uvicorn integration. Read only the references relevant to the task, but always check the compatibility and deprecation notes before upgrading. Coverage IDs: `pydantic-2.11.2`, `2025-06`, `2025-07`, `2025-09`, `pydantic-2.12-guide`, `pydantic-2.12.0`, `2025-10`, `2025-11`, `2025-12`, `2026-02`, `2026-03`, `2026-07`. ## Reference index | Reference | Topics | | --- | --- | | [upgrading-and-compatibility.md](references/upgrading-and-compatibility.md) | Python, Pydantic, Starlette, and httpx constraints; package extras; migration bridges; removals and deprecations | | [dependency-injection.md](references/dependency-injection.md) | `yield` scopes and teardown, caching, callable dependencies, annotation resolution, injected responses | | [requests-and-security.md](references/requests-and-security.md) | Forms and parameter models, strict JSON media types, tagged unions, authentication status and OpenAPI scopes | | [responses-and-streaming.md](references/responses-and-streaming.md) | Model serialization, JSON Lines, raw streaming, SSE, response annotations, byte schemas | | [openapi-and-pydantic.md](referenc...