Restore missing cards template

[LoveleshJain]

Making another type of change?

• I am fixing a bug / broken file, not submitting a card.
• This PR restores the missing cards/template.html file from git history.
• No other files have been changed.

What changed?

Restored cards/template.html, which was accidentally renamed instead of copied in PR #4681.

This restores the starter template required by the README for new contributors.

Resolves #4691

[github-actions]

Hi @LoveleshJain! 👋

It looks like you submitted cards/template.html itself rather than a copy of it.

Please copy cards/template.html to cards/your-github-username.html (using your actual GitHub username as the filename), fill it in, and submit that file instead.

[LoveleshJain]

The bot is treating this PR as a card submission, but this PR is intended to fix issue #4691.

Issue #4691 specifically requests restoring cards/template.html from git history because the file was accidentally renamed instead of copied.

I have not submitted a personal contributor card. The PR only restores the missing template file as requested by the issue.

The Validate Card PR check is therefore failing because it expects a cards/<username>.html card, while this PR is a non-card bug fix.

Could the validation workflow be adjusted/allowed for this issue, or could a maintainer confirm the preferred way to submit this fix?