Displays: 2.3 s to list two rows and no word on what a display is — make it fast and clear, or fold it into boards #11007

Owner, 2026-11-10: "packs and displays are bad." He said earlier: "im clicking around in displays and its getting really slow" and "im a little confused on what it is tbh." #10445 (fast everywhere, displays first) closed, but:

/displays today:

• It takes 2.3 s on the server (curl, signed in, 18:3xZ) to list two rows: "Games Shelf" and "Real estate desk".
• The only columns are Title, Layout and Repository.
• There's no picture of any display, and nothing that says what a display is or why you'd make one.

Done when:

1. Fast: /displays and every display render in under 200 ms on the server, with the budget enforced by a test (the #10445 time budget, applied to these routes). Find what costs the 2.3 s and name it in the pull.
2. Says what it is: one plain sentence at the top. Each display is a card with a live thumbnail, the repo it reads from, and "open full screen".
3. Earns its place: if a display is just a board or a layout of an app, fold it into that (Boards or the app page) and redirect /displays there. Don't keep a third noun. The pull states which way it went and why.
4. Proof:

- Server timings before and after. - Phone and desktop screenshots. - A cold reader can say what a display is in one sentence.

Under P12 Files and data (#10264).