Add enable_autolog_hparams argument to Trainer.

[duydl]

What does this PR do?

This PR provides flexibility for users who prefer to handle hyperparameter logging differently.

• Adds the enable_autolog_hparams argument to Trainer, allowing users to disable automatic logging of hyperparameters.
• Updates the documentation with examples demonstrating how to manually log hyperparameters when enable_autolog_hparams=False.

Possibly address #19889 .

No breaking changes.

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📚 Documentation preview 📚: https://pytorch-lightning--20593.org.readthedocs.build/en/20593/

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 79%. Comparing base (a0134d2) to head (2be8ead).
Report is 113 commits behind head on master.

❗ There is a different number of reports uploaded between BASE (a0134d2) and HEAD (2be8ead). Click for more details.

HEAD has 321 uploads less than BASE

Flag	BASE (a0134d2)	HEAD (2be8ead)
cpu	96	24
lightning	61	15
pytest	51	0
python3.11	24	6
python3.10	24	6
python	12	3
lightning_fabric	20	0
gpu	3	0
python3.12.7	36	9
pytorch2.1	12	6
pytorch_lightning	18	9
pytest-full	48	24
pytorch2.2.2	6	3
pytorch2.5	6	3
pytorch2.3	6	3
pytorch2.4.1	6	3
pytorch2.5.1	6	3
pytorch2.6	6	3

Additional details and impacted files

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##           master   #20593     +/-   ##
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- Coverage      88%      79%     -9%     
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  Files         267      264      -3     
  Lines       23373    23320     -53     
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- Hits        20483    18374   -2109     
- Misses       2890     4946   +2056     

[duydl]

@Borda Thank you. Please merge when convenient.

[Borda]

@lantiga mind sharing your point of view on this new Trainer's flag?

[lantiga]

Thank you @duydl, I'm good with the new argument.