- Add flood calibration task to re-learn link models from historical river levels.
- Introduce flood prediction task to evaluate calibrated links and send alerts based on upstream readings.
- Create utility functions for flood prediction, including model calibration and exceedance event detection.
- Implement river station utilities for parsing sensor data and calculating distances.
- Add tests for flood calibration, prediction, river levels, and utility functions to ensure functionality and reliability.

- index.html: self-contained, dependency-free simulation of an upstream->downstream
  flood with animated map, hydrograph chart, step indicator and predicted-vs-real
  arrival; real Idice/Reno parameters; carries a 'not an official forecast' disclaimer.
- modello-predittivo-piene.pdf: plain-language explainer of the empirical model,
  the 4 phases, the monitored stations, the backtest results and the usage limits.