feat: add forecast vs actual comparison analysis endpoint

[prashantpandeygit]

Pull Request

Description

added a new endpoint as source/region/forecast/vs-actual that can compare forecasted and actual power generated values side by side, calculates error metrics (error, absolute error, percent error), also adds stats with MAE,ME,RMSE, min/max error, if include_summary=true is given in the endpoint, done by new class ForecastActualComparison in endpoint_types.py

does not affect any data processing as endpoint results are not stored, they are only returned (read only endpoint)

How Has This Been Tested?

tested with dummy backend with api testing, output is attached below

and if include_summary=true , at the end of the response summary is returned as attached below

If your changes affect data processing, have you plotted any changes? i.e. have you done a quick sanity check?

• Yes

Checklist:

• My code follows OCF's coding style guidelines
• I have performed a self-review of my own code
• I have made corresponding changes to the documentation
• I have added tests that prove my fix is effective or that my feature works
• I have checked my code and corrected any misspellings