Add Root Mean Squared Error (RMSE) metric to pydeepflow.metrics (#111)

[darshbaxi]

Description

This PR adds the Root Mean Squared Error (RMSE) metric for regression tasks. RMSE is a widely used evaluation metric that measures the average magnitude of errors between predicted and actual values.

Features added:

• root_mean_squared_error(y_true, y_pred) function
• Unit test in tests/test_metrics.py with example calculation

Changes Included

1. New Metric Function:

   • Added root_mean_squared_error(y_true, y_pred) in pydeepflow.metrics.
   • Computes RMSE for regression tasks using the formula:
     [
     \text{RMSE} = \sqrt{\frac{1}{n} \sum_{i=1}^{n} (y_i - \hat{y}_i)^2}
     ]

2. Unit Tests:

   • Added test_root_mean_squared_error in tests/test_metrics.py.
   • Validates the RMSE calculation with example data:

     y_true = [3, -0.5, 2, 7]
     y_pred = [2.5, 0.0, 2, 8]
     RMSE = 0.6123724356957945

closes #111

[ravin-d-27]

Hi @darshbaxi ! good work! would be great if you resolve the merge conflicts, I'll be happy to merge!

[darshbaxi]

Hey! @ravin-d-27, I’ve resolved the merge conflicts.

[ravin-d-27]

Hey @darshbaxi ! Thank you!