Improve RichProgreasBar speed performance

[GdoongMathew]

What does this PR do?

Attempt to fix #13937

Benchmark Results are as below

master
    === Benchmark Results ===
    Version      No Rich (s)    With Rich (s)
    ---------  -------------  ---------------
    2.6.0.dev          7.945           13.089

master auto-refresh enabled, 33 updates / second
    === Benchmark Results ===
    Version      No Rich (s)    With Rich (s)
    ---------  -------------  ---------------
    2.6.0.dev          7.605             7.09

this branch
    === Benchmark Results ===
    Version      No Rich (s)    With Rich (s)
    ---------  -------------  ---------------
    2.6.0.dev          7.676            8.345

Key changes:

1. Conditional refresh
   CustomProgress.refresh now only calls its superclass method when running in interactive mode. This change is critical for performance since in most cases, we only need to notify the refresh thread rather than performing a full refresh.
2. No threading.Event for custom _RefreshThread
   Using Event would introduce unnecessary locking overhead. Since acquiring and releasing locks are relatively expensive here, this approach didn’t yield any speed improvement.
3. Auto-refresh side effects
   Simply enabling auto_refresh would revert Add refresh_rate to RichProgressBar #10497 and bring back pdb - based debugging with RichProgressBar doesn't show input #10607, which causes pdb unusable when using RichProgressBar.

TBH, I’m not entirely sure if this is the best solution, but I haven’t found another way to improve performance without undoing prior fixes.
Given that we’re now defaulting to rich-based progress bars and model summaries when rich is installed, I think this could still be quite a beneficial improvement — happy to hear thoughts or alternative ideas.

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---

📚 Documentation preview 📚: https://pytorch-lightning--21321.org.readthedocs.build/en/21321/

[codecov]

Codecov Report

❌ Patch coverage is 97.14286% with 1 line in your changes missing coverage. Please review.
✅ Project coverage is 79%. Comparing base (d046a96) to head (3e2a851).
✅ All tests successful. No failed tests found.

❗ There is a different number of reports uploaded between BASE (d046a96) and HEAD (3e2a851). Click for more details.

HEAD has 108 uploads less than BASE

Flag	BASE (d046a96)	HEAD (3e2a851)
cpu	54	27
python	6	3
lightning_fabric	12	0
pytest	27	0
python3.12.7	18	9
lightning	30	15
python3.11	12	6
python3.10	12	6
python3.12	6	3

Additional details and impacted files

@@            Coverage Diff            @@
##           master   #21321     +/-   ##
=========================================
- Coverage      87%      79%     -8%     
=========================================
  Files         269      266      -3     
  Lines       23744    23722     -22     
=========================================
- Hits        20569    18703   -1866     
- Misses       3175     5019   +1844     

[justusschock]

Looks great so far!
One minor question: can we make this configurable? so we/users can easily reduce this even more if required?

[GdoongMathew]

What do you think about reusing the original _RefreshThread.refresh_per_second, then exposing it as a configurable argument in the RichProgressBar callback.

One thing to note, this PR would also nullify the current refresh_rate argument, since we are now auto-refreshing the progress with refresh_per_second frequency.

[justusschock]

couldn't we use the refresh_rate argument instead then? But yeah generally something like that I had in mind :)

[GdoongMathew]

Yes, that works. I believe this is also related to the discussion mentioned here. I agree that we should keep using refresh_rate in this case, as long as we’re okay with updating its description, since it'll now represent the updates per second rather than current update frequency in number of batches?