[DOC] Improve documentation homepage with feature overview and quick example

[vinitjain2005]

Reference Issues/PRs

Closes #2176

What does this implement/fix? Explain your changes.

This PR improves the documentation homepage in docs/source/index.rst.

Changes made:

• Added a Key Features section to highlight the main capabilities of the library.
• Added a Quick Example section to help new users understand the basic workflow.
• Fixed wording and consistency issues such as replacing timeseries with time series.
• Corrected a small grammar issue in the installation sentence.

These updates improve readability and make onboarding easier for first-time users.

What should a reviewer concentrate their feedback on?

• Whether the new Key Features section is appropriate for the documentation landing page.
• Whether the Quick Example clearly demonstrates a minimal usage workflow.
• Wording, formatting, and placement of the new documentation sections in docs/source/index.rst.

Did you add any tests for the change?

No new tests were added because this PR only updates documentation.

Any other comments?

This is a documentation-only change intended to improve the homepage experience for new users and contributors.

PR checklist

• The PR title starts with either [ENH], [MNT], [DOC], or [BUG]. [BUG] - bugfix, [MNT] - CI, test framework, [ENH] - adding or improving code, [DOC] - writing or improving documentation or docstrings.
• Added/modified tests
• Used pre-commit hooks when committing to ensure that code is compliant with hooks. Install hooks with pre-commit install.
  To run hooks independent of commit, execute pre-commit run --all-files

Github: @vinitjain2005

[vinitjain2005]

@phoeenniixx @PranavBhatP @benHeid @fkiraly @fnhirwa @jdb78 @yarnabrina please review and merge

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
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Additional details and impacted files

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