# What does this PR do?
Consolidates provider data context handling into middleware, eliminating
duplication between FastAPI router routes and legacy @webmethod routes.
Closes#4366
## Test Plan
Added unit test suite `test_test_context_middleware`, specifically
`test_middleware_extracts_test_id_from_header` to validate the expected
behavior.
```
❯ ./scripts/unit-tests.sh tests/unit/
```
Integration of the middleware test context with the `files` FastAPI
router migration from
[pull/4339](https://github.com/llamastack/llama-stack/pull/4339).
```
❯ git switch migrate-files-api
Switched to branch 'migrate-files-api'
❯ git rebase fix-test-ctx-middleware
Successfully rebased and updated refs/heads/migrate-files-api.
❯ ./scripts/integration-tests.sh --inference-mode replay --suite base --setup ollama --stack-config server:starter --subdirs files
```
Signed-off-by: Matthew F Leader <mleader@redhat.com>
