fix(local): remove duplicate creationflags in _run_bash() on Windows

[EloquentBrush0x]

What does this PR do?

Root cause: #28874 added _popen_kwargs = {"creationflags": windows_hide_flags()} if _IS_WINDOWS else {} and **_popen_kwargs to the subprocess.Popen call in LocalEnvironment._run_bash(), but did not remove the pre-existing explicit argument:

creationflags=subprocess.CREATE_NO_WINDOW if _IS_WINDOWS else 0,

On Windows, Python raises TypeError: Popen.__init__() got multiple values for keyword argument 'creationflags' on every shell command execution — _run_bash() is completely broken.

Fix: remove the stale explicit creationflags= argument so **_popen_kwargs is the sole source of creationflags, matching the pattern already applied correctly in tools/process_registry.py (line 566) by the same PR.

Related Issue

Regression introduced in #28874.

Type of Change

• 🐛 Bug fix

Changes Made

• tools/environments/local.py: remove duplicate creationflags=subprocess.CREATE_NO_WINDOW if _IS_WINDOWS else 0 keyword argument from subprocess.Popen call in _run_bash() (-1 line)

How to Test

python3.11 -m pytest tests/tools/test_local_env_windows_msys.py tests/tools/test_local_env_blocklist.py -v --override-ini="addopts="

Checklist

• Contributing Guide read | Conventional Commits | No duplicate PR
• Single fix only | Platform: macOS
• Docs — N/A | Cross-platform — Windows crash fix

[teknium1]

Thanks for catching this Windows regression. This has since been fixed on main by the same one-line change, so I’m closing this as implemented on main.

Evidence from this automated hermes-sweeper review:

• tools/environments/local.py:593 on current main builds _popen_kwargs = {"creationflags": windows_hide_flags()} if _IS_WINDOWS else {}.
• tools/environments/local.py:605-606 passes cwd=_popen_cwd, **_popen_kwargs to subprocess.Popen() with no duplicate explicit creationflags= kwarg.
• Commit 05f02640e1f763afb7afdae4efe6b450016a908f removes exactly the stale creationflags=subprocess.CREATE_NO_WINDOW if _IS_WINDOWS else 0 line from LocalEnvironment._run_bash().
• That fix was merged via PR fix(windows): drop duplicate creationflags kwarg in LocalEnvironment run_bash #29059 as merge commit 62713c8b8926c5280a0dfbfcf42cf2c07ec8a047 and is contained in current origin/main.