fix(engine): include async, type annotations, and class methods in Python public surface hashes (#76)

[Cid-oe]

Summary

Fixes #76 by ensuring Python public API surface serialization preserves async vs sync distinctions, argument type annotations, return types, and class method signatures.

Changes

• Updated argument formatting to include type annotations (:type) alongside default values in function_signature.
• Distinguished async functions with py:async_function: prefix (and included return annotations :return_type).
• Included public class methods (and __init__) in class surface representations as py:class_member:<class>.<method|async_method>:<name>(<signature>):<returns>.
• Updated surface_part_name to resolve top-level names for py:async_function: and py:class_member:.
• Updated existing test expectation in tests/module-resolution.test.mjs and added regression test for bug bug: [P2] Python public API surface hashes ignore async, type annotation, and method changes #76 in tests/review-regressions.test.mjs.

Closes #76

[premiuslol]

Reviewed exact head 8acf87c09cfb0c14ac7cb8c980060539a0a41de5 against #76. The implementation preserves async/sync distinctions, argument and return annotations, and public class method signatures in the Python surface while keeping body-only changes out of the hash. Local validation on this exact head: npm run build passed; the combined module-resolution/review-regression run passed 89/91 with 1 skip, including the new bug #76 regression and the existing Python public-surface test. The sole failure was the known Windows interpreter-alias case in bug #54 (python resolving to the Microsoft Store stub), not a failure of this patch. I did not find a correctness issue within the requested scope.

[Cid-oe]

Closing in favor of the updated, signed-off revision in #83.