Make trace `names` field directly linked to the names present in the trace

@riccardofelluga is already working on this.

Since Oct 8, 2024.

## 🐛 Bug

As of now, if you run something like this:

```python
import thunder

import torch
import torch.nn as nn

class MyModel(nn.Module):
def __init__(self) -> None:
super().__init__()
self.layers = nn.Sequential(
nn.Linear(10, 10),
nn.ReLU(),
nn.Linear(10, 10)
)

def forward(self, x):
return self.layers(x)

a = torch.randn((10, 10), requires_grad=True, device="cuda")
m = MyModel().to("cuda")

jm = thunder.jit(m)
jm(a)

print(thunder.last_traces(jm)[-1].names)
print(thunder.last_traces(jm)[-1].bound_symbols)
```

the list of names does not correspond with the names present in the trace.

### Expected behavior

What should be is that the names are only the ones present in the trace and nothing more. This has effect on registering new symbols in the trace where names conflicts can happen even tho there are no bound symbols with the same name in the trace due to the check here:

https://github.com/Lightning-AI/lightning-thunder/blob/fceb64efc93a80a27d38b8e84f0e2b5f132f3d2f/thunder/core/trace.py#L170-L175