Wrap functions into app.py and add .gitignore for unnecessary files

[siddharth7113]

Pull Request

Description

This PR wraps the forecast-related functionalities into a single app.py script and adds a .gitignore file to the repository to prevent tracking unnecessary files.

• app.py: Implements modular functions (get_forecast, format_forecast, save_forecast) to fetch, format, and save NESO solar forecast data.
• .gitignore: Ensures unnecessary files such as Python bytecode, test cache, build artifacts, and logs are ignored.

Fixes: #6 and #14

How Has This Been Tested?

1. Ran the app.py script manually to verify the following:
   • Forecast data is fetched correctly using placeholder resource IDs.
2. Verified that the .gitignore prevents unnecessary files from being tracked.

• Yes

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

• Yes
  • Logs were reviewed to ensure steps executed correctly.

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 (tests for .gitignore are implicit)
• I have checked my code and corrected any misspellings

[peterdudfield]

Happy to merge?