feat(python): add package cooldown and pyrefly

[slbotbm]

Which issue does this PR close?

Closes #3246

Rationale

• 7 day cooldown was needed to harden supply chain
• pyrefly replaces mypy as the type checker

What changed?

• pyrefly was added to the sdk, examples, and bdd directories. It was also added in precommit and the ci. The resulting changes in python files are errors that it caught.
• 7 day cooldown was added to all three pyproject.toml's

Local Execution

• Passed
• Pre-commit hooks ran

AI Usage

If AI tools were used, please answer:

1. Which tools? codex
2. Scope of usage? mistake correction
3. How did you verify the generated code works correctly? verified manually
4. Can you explain every line of the code if asked? yes

[github-actions]

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 73.53%. Comparing base (0df7d38) to head (828a684).

Additional details and impacted files

@@             Coverage Diff              @@
##             master    #3323      +/-   ##
============================================
- Coverage     73.57%   73.53%   -0.05%     
  Complexity      943      943              
============================================
  Files          1241     1241              
  Lines        115147   115147              
  Branches      91634    91664      +30     
============================================
- Hits          84725    84676      -49     
- Misses        27574    27586      +12     
- Partials       2848     2885      +37     

Components	Coverage Δ
Rust Core	74.50% <ø> (-0.02%)	⬇️
Java SDK	58.44% <ø> (ø)
C# SDK	70.14% <ø> (-0.63%)	⬇️
Python SDK	81.06% <ø> (ø)
Node SDK	91.53% <ø> (ø)
Go SDK	40.20% <ø> (ø)
see 27 files with indirect coverage changes

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