[dbrattli]

Adds support for FSharp.Core’s existing Async.TryCancelled API to JavaScript/TypeScript, Python, and BEAM. Calls currently compile to runtime functions that do not exist.

The cancellation handler receives the original exception before cancellation continues. Success and ordinary errors pass through unchanged, and an exception from the handler does not replace cancellation. Nested handlers are installed before cancellation is checked; JavaScript and Python preserve the existing trampoline when unwinding them.

[github-actions]

Python Type Checking Results (Pyright)

Metric	Value
Total errors	33
Files with errors	4
Excluded files	4
New errors	✅ No

Excluded files with errors (4 files)

These files have known type errors and are excluded from CI. Remove from pyrightconfig.ci.json as errors are fixed.

File	Errors	Status
temp/tests/Python/test_hash_set.py	18	Excluded
temp/tests/Python/test_applicative.py	11	Excluded
temp/tests/Python/test_nested_and_recursive_pattern.py	2	Excluded
temp/tests/Python/fable_modules/thoth_json_python/encode.py	2	Excluded