[docs-website]: add branded 404 page to docs site

[skools-here]

What has changed?

This PR adds a custom, branded 404 page to the Keploy docs website.

This PR Resolves #(3441)
keploy/keploy#3441

Type of change

Please delete options that are not relevant.

• Documentation update (if none of the other choices apply).

How Has This Been Tested?

Ran npm run start and verified the custom 404 page renders for unknown /docs/* routes.

Ran npm run build followed by npm run serve to verify production behavior.

Confirmed the page layout, navigation buttons, and logo render correctly.

Checklist:

• My code follows the style guidelines of this project.
• I have performed a self-review of my own code.

[github-actions]

Thank you and congratulations 🎉 for opening your very first pull request in keploy

[Achanandhi-M]

Hey @skools-here , the changes look really good, However, from our side, we don’t want to include any bunny image or custom design for the 404 page.

If a user types a 404 URL or visits a non-existent page, it should simply redirect to /docs (the docs homepage). Please update it accordingly. Also please fix the Copilot suggestions. The pipelines are failing, please try to fix it

[skools-here]

@Achanandhi-M yes I am working on changes !

[skools-here]

Hello @Achanandhi-M I fixed the changes you said and also pipelines error is gone can you please take a look !

[amaan-bhati]

Thank you for following through on the earlier feedback and getting the pipelines green! We really appreciate the effort you put in.

We are going to close this PR as there has been no activity since January, and a separate 404 page PR has been open and under active discussion more recently. To avoid duplicate work landing, it makes more sense to converge on that one.

Your work here was not wasted - the direction of redirecting to the docs homepage for 404 errors is exactly the approach we want, and that spirit carries forward. We hope you will keep contributing to Keploy! There are many open issues across the repo where your help would be valuable. Feel free to reach out on Slack if you have questions or want guidance on what to work on next. Thank you for your time and energy!