test: Test fixes

[gavin-aguiar]

Description

Speed up CI pipelines and fix flaky / failing tests

Performance

• Switch pip → uv in all install scripts and CI templates ( install-dependencies.sh ,  test-sdk.sh ,  test-extensions.sh ,  ci-dependency-check.yml ,  ci-fc-tests.yml ) for faster dependency resolution. Batched the worker installs into a single resolver pass.
• Enable real pytest-xdist parallelism: unit tests  -n auto , emulator tests  -n 2 , E2E kept serial (shared Azure resources).  --dist loadfile  alone was previously a no-op without  -n .
• Build only the WebHost project instead of the whole  WebJobs.Script.sln  (~2.7x faster, far less disk, avoids restoring unrelated projects from the internal feed). Added  set -e  to  test-setup.sh  so build failures surface instead of being masked.
• Removed unused dev deps ( ptvsd ,  pre-commit ,  pytest-sugar ,  pytest-randomly ) from all three  pyproject.toml .
• Split the install step into separate "Python deps (uv)" and "webhost build (dotnet)" stages so timings are visible.

Test reliability

• Fixed flaky  test_unhandled_error  (all 3 variants): the traceback is forwarded to the host asynchronously, so the log-check snapshot raced it. Added  WebHostTestCase.wait_for_host_log()  to wait for the line before asserting.
• Replaced the racy  time.sleep(10)  webhost startup with a real readiness probe polling  /admin/host/status  for  Running  (with master key).
• Fixed Azurite "InvalidHeaderValue" in emulator tests via  --skipApiVersionCheck --loose ; added a ServiceBus emulator readiness wait.

Python 3.14 / version compatibility

• Made  runtimes/v{1,2}  installs and the uamqp-based ServiceBus binding install conditional (uv enforces  requires-python ); loosened the  fastapi  pin to resolve a  dev  vs  test-http-v2  conflict.
• Gated  TestServiceBusSDKFunctions  to Python 3.13 only (the binding needs protobuf ≥6.32/grpcio ≥1.74, incompatible with the ≤3.12 worker's pins).

New coverage

• Added a Flex Consumption test verifying blob SDK (deferred) bindings load under Flex ( BlobSdkBindings.zip  fixture +  test_blob_sdk_bindings , gated to 3.14).

Fixes #

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Pull Request Checklist

Host-Worker Contract

• Does this PR impact the host-worker contract (e.g., gRPC messages, shared interfaces)?
  • If yes, have the changes been applied to:
    • azure_functions_worker (Python <= 3.12)
    • proxy_worker (Python >= 3.13)
  • If no, please explain why:

Worker Execution Logic

• Does this PR affect worker execution logic (e.g., function invocation, bindings, lifecycle)?
  If yes, please answer the following:

Python Version Coverage

• Does this change apply to both Python <=3.12 and 3.13+?
• If yes, have the changes been made to:
  • azure_functions_worker (Python <= 3.12)
  • runtimes/v1 / runtimes/v2 (Python >= 3.13)
• If no, please explain why:

Programming Model Compatibility (for Python 3.13+)

• Does this change apply to both:
  • V1 programming model (runtimes/v1)?
  • V2 programming model (runtimes/v2)?
• Explanation (if limited to one model):