[vatsrahul1001]

Manual backport of #75689 to v3-4-test.

The auto-backport conflicted because #75689 was built on two features that are not on v3-4-test (both 3.5.0-scoped and deliberately kept off the branch). This is a pruned subset that drops the parts depending on them and keeps the FastAPI/cadwyn bump plus the lazy-router + native-OpenTelemetry-disable adaptations.

Dropped (absent from v3-4-test):

• REST API metrics (Add REST API metrics #64523): common/http_metrics.py + its test + the HttpMetricsMiddleware import/tests in app.py / test_app.py.
• Dag-processor scoped Execution API access (Add scoped Execution API access for Dag processors #74370): the token-scope test fixtures (JOB_UNCHECKED_ROUTES, DAG_PROCESSOR_* dicts) and TestDagProcessorMessageRoutes in test_token_scope_boundaries.py.

Kept / adapted:

• fastapi>=0.142 (resolves 0.161) + cadwyn>=8.1 in airflow-core and task-sdk (+ uv.lock).
• NATIVE_TELEMETRY_DISABLED applied to all FastAPI apps (core, execution, log server).
• Lazy-router adaptation (iter_route_contexts / iter_api_routes) in execution_api/app.py and the remaining execution-API tests, including test_token_scope_boundaries.py::TestTokenScopeBoundaries and the new test_fastapi_native_telemetry_records_no_spans.
• taskinstance.py Discriminator(...) change.

Verified locally: no conflict markers, py_compile clean, and the remaining source references only symbols present on v3-4-test (require_auth, _REQUEST_SCOPE_TOKEN_KEY, InProcessExecutionAPI) plus fastapi 0.161's iter_route_contexts. Full execution-API test validation runs here in CI under fastapi 0.161.

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• Yes — Claude Code (Opus 4.8)

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[github-actions]

⚠️ 2 job(s) of attempt 1 were stopped because AWS reclaimed their EC2 Spot instances. These are not test failures.

• Special tests / Latest Boto test: core / core:LatestBoto-Postgres:14:3.11:Core...Serialization
• Special tests / Pendulum2 test: core / core:Pendulum2-Postgres:14:3.11:Core...Serialization

RunsOn re-runs them automatically when the run finishes; no action is needed.