fix: Make OpenAPI /docs path work again

* The main fix is in eval_metrics.py
* Removed some deprecated paths in the FastAPI server
* Added a unit test to catch future breakages
* Bump fastapi version to be 0.124.1 to capture the fix in https://github.com/fastapi/fastapi/pull/14482
* Removed the upper-bound restriction on fastapi version which was used to temporarily fix the issue

Fixes #3173

Co-authored-by: Liang Wu <wuliang@google.com>
PiperOrigin-RevId: 861867708

src/google/adk/cli/adk_web_server.py

@@ -946,27 +946,6 @@ class AdkWebServer:
             detail=str(ve),
         ) from ve
 
-    @deprecated(
-        "Please use create_eval_set instead. This will be removed in future"
-        " releases."
-    )
-    @app.post(
-        "/apps/{app_name}/eval_sets/{eval_set_id}",
-        response_model_exclude_none=True,
-        tags=[TAG_EVALUATION],
-    )
-    async def create_eval_set_legacy(
-        app_name: str,
-        eval_set_id: str,
-    ):
-      """Creates an eval set, given the id."""
-      await create_eval_set(
-          app_name=app_name,
-          create_eval_set_request=CreateEvalSetRequest(
-              eval_set=EvalSet(eval_set_id=eval_set_id, eval_cases=[])
-          ),
-      )
-
     @app.get(
         "/apps/{app_name}/eval-sets",
         response_model_exclude_none=True,
@@ -982,19 +961,6 @@ class AdkWebServer:
 
       return ListEvalSetsResponse(eval_set_ids=eval_sets)
 
-    @deprecated(
-        "Please use list_eval_sets instead. This will be removed in future"
-        " releases."
-    )
-    @app.get(
-        "/apps/{app_name}/eval_sets",
-        response_model_exclude_none=True,
-        tags=[TAG_EVALUATION],
-    )
-    async def list_eval_sets_legacy(app_name: str) -> list[str]:
-      list_eval_sets_response = await list_eval_sets(app_name)
-      return list_eval_sets_response.eval_set_ids
-
     @app.post(
         "/apps/{app_name}/eval-sets/{eval_set_id}/add-session",
         response_model_exclude_none=True,
@@ -1142,22 +1108,6 @@ class AdkWebServer:
       except NotFoundError as nfe:
         raise HTTPException(status_code=404, detail=str(nfe)) from nfe
 
-    @deprecated(
-        "Please use run_eval instead. This will be removed in future releases."
-    )
-    @app.post(
-        "/apps/{app_name}/eval_sets/{eval_set_id}/run_eval",
-        response_model_exclude_none=True,
-        tags=[TAG_EVALUATION],
-    )
-    async def run_eval_legacy(
-        app_name: str, eval_set_id: str, req: RunEvalRequest
-    ) -> list[RunEvalResult]:
-      run_eval_response = await run_eval(
-          app_name=app_name, eval_set_id=eval_set_id, req=req
-      )
-      return run_eval_response.run_eval_results
-
     @app.post(
         "/apps/{app_name}/eval-sets/{eval_set_id}/run",
         response_model_exclude_none=True,
@@ -1251,28 +1201,6 @@ class AdkWebServer:
       except ValidationError as ve:
         raise HTTPException(status_code=500, detail=str(ve)) from ve
 
-    @deprecated(
-        "Please use get_eval_result instead. This will be removed in future"
-        " releases."
-    )
-    @app.get(
-        "/apps/{app_name}/eval_results/{eval_result_id}",
-        response_model_exclude_none=True,
-        tags=[TAG_EVALUATION],
-    )
-    async def get_eval_result_legacy(
-        app_name: str,
-        eval_result_id: str,
-    ) -> EvalSetResult:
-      try:
-        return self.eval_set_results_manager.get_eval_set_result(
-            app_name, eval_result_id
-        )
-      except ValueError as ve:
-        raise HTTPException(status_code=404, detail=str(ve)) from ve
-      except ValidationError as ve:
-        raise HTTPException(status_code=500, detail=str(ve)) from ve
-
     @app.get(
         "/apps/{app_name}/eval-results",
         response_model_exclude_none=True,
@@ -1285,19 +1213,6 @@ class AdkWebServer:
       )
       return ListEvalResultsResponse(eval_result_ids=eval_result_ids)
 
-    @deprecated(
-        "Please use list_eval_results instead. This will be removed in future"
-        " releases."
-    )
-    @app.get(
-        "/apps/{app_name}/eval_results",
-        response_model_exclude_none=True,
-        tags=[TAG_EVALUATION],
-    )
-    async def list_eval_results_legacy(app_name: str) -> list[str]:
-      list_eval_results_response = await list_eval_results(app_name)
-      return list_eval_results_response.eval_result_ids
-
     @app.get(
         "/apps/{app_name}/metrics-info",
         response_model_exclude_none=True,