Add pr template

[Mansi2007275]

Closes #179

Added .github/pull_request_template.md to standardize pull request
contributions. The template is lightweight and guides contributors to include:

• A summary of changes
• Related issue number
• Type of change
• Testing steps
• DCO sign-off checklist

Kept it minimal as discussed in issue #179 to avoid burdening contributors.

[Mansi2007275]

Hi @pleia2 — PR is ready for review!
This adds issue templates (closes #180) and also
includes the PR template (closes #179) as both were assigned to me.

[pleia2]

I'm only seeing the changes from #304 rather than the PR template change. Can you separate these changes and see where the template change ended up?

[Mansi2007275]

Hi @pleia2 — apologies for the delay, and thank you for your patience!
I've cleaned up the branch and it now contains only the PR template change (1 commit, 1 file) please review this and see this whenever you get chance ..

[pleia2]

It's still showing me "Whitespace-only changes." rather than the template content when I go to review it 🤔 Can you take another look?

Thanks again for your time on this!