fix: resolve 4 bugs in leetcode-ranking

[saurabhhhcodes]

Description

This PR fixes real bugs found in the codebase:

• Prevented interval leak: repeated mounts now clear the previous interval before scheduling a new one.
• Fixed default sort: .sort() coerces elements to strings, so [10, 9, 2] sorts as [10, 2, 9]; numeric comparator sorts correctly.
• Added rejection handler to Promise.all: an unhandled rejection in any input promise previously crashed silently.
• Replaced innerHTML assignment with textContent: prevents HTML injection / XSS and is faster since it does not parse markup.

Type of Change

• Bug fix (non-breaking change fixing an issue)

How Has This Been Tested?

• Local manual testing

Checklist

• My code follows the style guidelines
• I have performed a self-review

Related Issue

Ref: #418

[github-actions]

Thank you for submitting a pull request.

Please ensure your changes comply with the project's contribution guidelines and that all workflow checks pass successfully.

Formatting and Branching

• Please confirm you have formatted your code locally using npx prettier --write . before requesting a review.
• Ensure this PR is made from a feature/* branch and not main.

Note: This project is currently maintained by a solo maintainer, so reviews and responses may sometimes take a little time. Thanks for your patience.

[jagdish-15]

Closing as spam.