Implement todos tensorboard

[KAVYANSHTYAGI]

What does this PR do?

Improves the test coverage for TensorBoardLogger by enhancing the test_tensorboard_log_graph suite:

 Adds parameterization to test both torch.nn.Module and lightning.pytorch.LightningModule via BoringModel from demos.boring_classes.

  Verifies that log_graph works correctly when the model is wrapped using _FabricModule.

  Confirms that batch_transfer_handler methods (_on_before_batch_transfer and _apply_batch_transfer_handler) are triggered during logging.

   Adds a descriptive skip reason for tests when TensorBoard is not available, to improve CI/debugging clarity.

This change ensures more robust and realistic validation of the logging graph functionality, especially for models that go through Fabric’s module wrapping and transfer pipeline.

Was this discussed/agreed via a GitHub issue? (not for typos and docs)no

Did you read the contributor guideline, Pull Request section?yes

Did you make sure your PR does only one thing, instead of bundling different changes together?yes

Did you make sure to update the documentation with your changes? (if necessary)no

Did you write any new necessary tests? (not for typos and docs)no

Did you verify new and existing tests pass locally with your changes?yes

Did you list all the breaking changes introduced by this pull request?yes

Did you update the CHANGELOG? (not for typos, docs, test updates, or minor internal changes/refactors)no

PR review

Anyone in the community is welcome to review the PR.

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📚 Documentation preview 📚: https://pytorch-lightning--20874.org.readthedocs.build/en/20874/

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 49%. Comparing base (ab7b118) to head (f36050e).
Report is 8 commits behind head on master.

❗ There is a different number of reports uploaded between BASE (ab7b118) and HEAD (f36050e). Click for more details.

HEAD has 1075 uploads less than BASE

Flag	BASE (ab7b118)	HEAD (f36050e)
cpu	263	27
python	30	3
lightning_fabric	60	14
pytest	135	30
python3.12.7	88	9
python3.10	58	6
lightning	147	16
python3.12	29	3
python3.11	58	6
pytorch2.1	29	0
pytorch_lightning	59	0
pytest-full	131	0
pytorch2.2.2	15	0
pytorch2.3	13	0
pytorch2.5	15	0
pytorch2.7	15	0
pytorch2.4.1	15	0
pytorch2.6	14	0
pytorch2.5.1	15	0

Additional details and impacted files

@@            Coverage Diff            @@
##           master   #20874     +/-   ##
=========================================
- Coverage      87%      49%    -38%     
=========================================
  Files         268      265      -3     
  Lines       23414    23358     -56     
=========================================
- Hits        20363    11407   -8956     
- Misses       3051    11951   +8900     

[KAVYANSHTYAGI]

One test now covers plain nn.Module and _FabricModule cases.

The other focuses on LightningModule with batch transfer hooks.

[Borda]

perfect, thank you @KAVYANSHTYAGI