Remove lib parameter from _raw_main and _setup

[semohr]

Description

The lib parameter on _raw_main and _setup was only used by the test harness. Rather than keep testing-specific logic in production code, this PR removes the parameter and updates the test harness to patch _open_library instead.

• Changelog. (Not needed as this is a purely internal factor imo)

[github-actions]

Thank you for the PR! The changelog has not been updated, so here is a friendly reminder to check if you need to add an entry.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 71.77%. Comparing base (e550482) to head (7f48672).
⚠️ Report is 4 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #6547      +/-   ##
==========================================
- Coverage   71.77%   71.77%   -0.01%     
==========================================
  Files         159      159              
  Lines       20531    20528       -3     
  Branches     3266     3264       -2     
==========================================
- Hits        14737    14734       -3     
  Misses       5105     5105              
  Partials      689      689              

Files with missing lines	Coverage Δ
beets/ui/__init__.py	82.11% <100.00%> (-0.13%)	⬇️

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[Copilot]

Pull request overview

PR remove lib param from CLI bootstrap (_raw_main / _setup). Goal: keep test-only hook out of prod code. grug like that idea.

Changes:

• Remove lib injection path from beets.ui._setup and beets.ui._raw_main; always open library via _open_library.
• Update test harness RunMixin.run_command to patch beets.ui._open_library instead of passing lib into _raw_main.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 2 comments.

File	Description
beets/ui/init.py	Drop lib argument from CLI internals and always close opened library.
beets/test/helper.py	Switch tests to patch _open_library and stub lib._close to keep shared lib alive.

Comments suppressed due to low confidence (1)

beets/ui/init.py:1000

• grug see main now need args always. packaging entrypoint beet = "beets.ui:main" call main() with no args, so runtime TypeError. make args optional (default None) and when None set to sys.argv[1:] before call _raw_main.

def main(args: list[str]) -> None:
    """Run the main command-line interface for beets. Includes top-level
    exception handlers that print friendly error messages.
    """
    if "AppData\\Local\\Microsoft\\WindowsApps" in sys.exec_prefix: