Group the metrics in Tensorboard

Nobody has claimed this yet.

### Bug description

I cannot understand what needs to be done to group the graphs for the same metric:

```python
self.log_dict(
dictionary={'losses/a': 0.1, 'losses/b': 0.2},
batch_size=1,
add_dataloader_idx=False,
prog_bar=False,
on_step=True,
on_epoch=False,
sync_dist=False,
rank_zero_only=True,
)

self.log(
name='losses/c',
value=0.3,
batch_size=1,
add_dataloader_idx=False,
prog_bar=False,
on_step=True,
on_epoch=False,
sync_dist=False,
rank_zero_only=True,
)

self.log(
name='losses/d',
value=0.3,
batch_size=1,
add_dataloader_idx=False,
prog_bar=False,
on_step=True,
on_epoch=False,
sync_dist=False,
rank_zero_only=True,
)
```

Result in:

I would really like to see all 4 lines on the same plot.

version: 2.6.1

### What version are you seeing the problem on?

v2.5

### Reproduced in studio

_No response_

### How to reproduce the bug

```python
self.log_dict(
dictionary={'losses/a': 0.1, 'losses/b': 0.2},
batch_size=1,
add_dataloader_idx=False,
prog_bar=False,
on_step=True,
on_epoch=False,
sync_dist=False,
rank_zero_only=True,
)

self.log(
name='losses/c',
value=0.3,
batch_size=1,
add_dataloader_idx=False,
prog_bar=False,
on_step=True,
on_epoch=False,
sync_dist=False,
rank_zero_only=True,
)

self.log(
name='losses/d',
value=0.3,
batch_size=1,
add_dataloader_idx=False,
prog_bar=False,
on_step=True,
on_epoch=False,
sync_dist=False,
rank_zero_only=True,
)
```

### Error messages and logs

```
# Error messages and logs here please
```

### Environment

Current environment

```
#- PyTorch Lightning Version: 2.6.1
#- PyTorch Version: 2.9.1
#- Python version: 3.12
#- OS: Linux
#- CUDA/cuDNN version: 13.0
#- How you installed Lightning: poetry
```

### More info

_No response_

cc @ethanwharris @lantiga

The report does not name a file or test. Start by reproducing the behavior with the provided self.log_dict and self.log calls, then trace the TensorBoard logging entry points; done means the four losses series appear together on one plot without changing the reported metric names.

Written by the indexing model from the issue text.