Keep finished hooks visible

[j178]

Closes #1953

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 92.19%. Comparing base (bce57a3) to head (7a695b1).
⚠️ Report is 1 commits behind head on master.

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #1967   +/-   ##
=======================================
  Coverage   92.18%   92.19%           
=======================================
  Files         116      116           
  Lines       23274    23287   +13     
=======================================
+ Hits        21455    21469   +14     
+ Misses       1819     1818    -1     

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[Copilot]

Pull request overview

This PR updates the hook-running progress UI so that hooks which finish early in a parallel priority group remain visible until the group’s final results are rendered, addressing issue #1953.

Changes:

• Track completed hook progress bars in the reporter instead of immediately clearing them on completion.
• Delay removal of completed hook bars until the priority group results are about to be printed (and on final completion).

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
crates/prek/src/cli/run/run.rs	Clears completed progress bars right before printing a priority group’s final rendered output.
crates/prek/src/cli/reporter.rs	Keeps finished hook progress bars visible (finish vs finish_and_clear), tracks them, and removes them later via clear_completed().