Title bar for pipeline details page

Description

Apply proposal from #20892 (closed) to pipeline detail pages as well.

Current:

Proposal

• Convert the second and third meta lines into a title, consistent with other pages.
• Render the Commit title and message as markdown, consistent with other pages.
• Move pipeline information to a system information box consistent with merge request pages, and hopefully a change we can propagate.
• Move Retry Failed, Cancel Running, and any other buttons (except Hide Pipeline Graph) to the title bar.

Design

The clipboard icon button tooltip should say "Copy commit SHA to clipboard"

Note: All SHA references should be set in monospaced fonts

Rewording of 1 of the system information lines: "for" to "from"

Links / references

• Related: #20892 (closed)