Hardcoded year in the price baseline

`get_averages_year()` in `src/hpc_eff/utils/energy_price.py` scrapes the yearly price baseline from a **hardcoded URL**:

```python
url = 'https://spotovaelektrina.cz/historicke-ceny/2025/1'
```

The year `2025` is frozen in the code. 
## Proposed fix

1. Build the URL from the current date instead of a constant: fetch `/{current_year}/1`.