[Mintlify] Fix landing page

Page link:

preview.bazel.build

Problem description (include actual vs expected text, if applicable):

Feedback from a fellow Googler:

"I feel that the current new design of the landing page looks incomplete without the hero section that we have on the current design. I strongly feel we should keep the hero section including the "{Fast, Correct} - Choose two" tagline, which has been the Blaze slogan historically. Keeping the "Install Bazel" button (or a similar "Get Started" button) would also be more intuitive, as it gives users an obvious starting point.

The landing page is also missing the footer that the other pages have."

I agree that we should fix these issues.

Where do you see this issue? (include link to specific section of the page, if applicable)

No response

Any other information you'd like to share?

No response