Proposed change

Probatio resolves to_field_list and to_openapi through a lazy import of probatio.codecs on first attribute access. Both are first reached from the event loop, where that import is a blocking call: one renders every config flow form, the other builds the tool schemas for a conversation turn.

Detected blocking call to import_module with args ('probatio.codecs',) inside the
event loop by integration 'http'

Resolve them in the package __init__, where probatio is already configured and which runs long before the loop exists. It costs 3.8 ms on top of importing probatio, and probatio.codecs pulls in no voluptuous of its own, so it is safe before install_as_voluptuous().

The test runs in a clean interpreter, like test_circular_imports.py. By the time an ordinary test runs, something has already imported the codecs and the assert would pass either way.

Type of change

• Dependency upgrade
• Bugfix (non-breaking change which fixes an issue)
• New integration (thank you!)
• New feature (which adds functionality to an existing integration)
• Deprecation (breaking change to happen in the future)
• Breaking change (fix/feature causing existing functionality to break)
• Code quality improvements to existing code or addition of tests

Additional information

• This PR fixes or closes issue: fixes Detected blocking call to import_module with args ('probatio.codecs',) inside the event loop by integration 'http' #183803
• This PR is related to issue:
• Link to documentation pull request:
• Link to developer documentation pull request:
• Link to frontend pull request:

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