Add Pyrefly Check PreCommit

[jrmccluskey]

Adds a pyrefly static type checking precommit to Beam, enforcing checks to avoid introducing new breakages.

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[gemini-code-assist]

Note

Gemini is unable to generate a summary for this pull request due to the file types involved not being currently supported.

[Abacn]

Consider adding an item in workflow/README.md (will be enforced after #37883)

[Abacn]

PythonLint -> Python_Pyrefly

[Abacn]

shall we use [self-hosted, ubuntu-20.04, small] ?

[github-actions]

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