Docs website brand refresh

[zahidalidev]

This PR includes the following updates:

1. UI Updates:

   • Modified the UI to align with the new design.

2. TierCallout Component:

   • Introduced a new TierCallout component for .mdx files.
   • Example usage:

     <TierCallout>
       Visit the [pricing page](https://about.sourcegraph.com/pricing) for up-to-date pricing.
       <user>
         This feature is available for Enterprise users with [premium support](https://about.sourcegraph.com/support).
       </user>
     </TierCallout>

3. New Layout Component:

   • Added a new component inside Layout featuring tabs and a video container.
   • Included demo content for now, which will be updated based on instructions.

[vercel]

@zahidalidev is attempting to deploy a commit to the Sourcegraph Team on Vercel.

A member of the Team first needs to authorize it.

[vercel]

The latest updates on your projects. Learn more about Vercel for Git ↗︎

Name	Status	Preview	Comments	Updated (UTC)
sourcegraph-docs	✅ Ready (Inspect)	Visit Preview	💬 Add feedback	Jan 28, 2025 7:07pm

[MaedahBatool]

@zahidalidev, one feedback: can we please remove the gradient from all the icons and replace it with the default orange base?

[zahidalidev]

@MaedahBatool I have updated the colours of icon as well.

[MaedahBatool]

@MaedahBatool I have updated the colours of icon as well.

Thanks a ton. I'll review it. :)

[MaedahBatool]

Thanks Zahid, for your help. I am merging this PR into our release branch. Any follow-up changes will be tackled later after the release. Let's go! 🚀