Listing stats

GAVRASM does a nice summary at the foot of a listing

```
Program             :       22 words.
Constants           :        0 words.
Total program memory:       22 words.
Eeprom space        :        0 bytes.
Data segment        :        0 bytes.
Compilation completed, no errors.
Compilation ended 29.06.2025, 11:41:36
```

I'd like something simillar