`LightningModule.on_train_batch_end` executes after `Callback.on_train_batch_end`

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### Outline & Motivation

Hi! In my `LightningModule`, I have a `on_train_batch_end` which performs some post-processing of the results from the `training_step` (for example logits normalisation and update metrics). Now I can callbacks with also `on_train_batch_end` method, which expects the model outputs to be normalised.
However, I find out that the execution order is "`LightningModule.training_step` -> `Callback.on_train_batch_end` -> `LightningModule.on_train_batch_end`", while I was expecting to be "`LightningModule.training_step` -> `LightningModule.on_train_batch_end` -> `Callback.on_train_batch_end`", which seems more natural to me.

I don't want to have this normalisation process in the `training_step`, because I want to have it as an `abstractumethod` so children classes overwrite the `training_step` and the `on_train_batch_end` can be supported out-of-the-box.

Concreate example:
Binary Segmentation model, `LightningModule.training_step` produces the model `logits`, in the `LightningModule.on_train_batch_end` I define how these will be denormalized and pass them to the metrics, and I have a callback `SegmentationWriter` which expects the predictions to be denomalized, to visualise and save them on disk. Note that I want to describe and execute the denormalisation process only once, so that the metrics and the segmentation writer will use the same one (and I dont want to repeat myself in the segmentation callback)

Question: is it intended or a specific reason which the `on_train_batch_end` callback method come first from the `LightningModule`, as for me it feels more natural the otherway around? Can I alter this order?

Thank you!

### Pitch

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### Additional context

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cc @justusschock @awaelchli @carmocca @borda

Start by tracing the training-loop dispatch for LightningModule.on_train_batch_end and Callback.on_train_batch_end. Add a focused test that records both hook calls and verifies the intended order, then confirm the existing callback behavior and document what the test establishes.

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