Card Builder controls for the groups of buttons

[nstarman]

Changing code or schema

What and why: the buttons became groups in #346 (buttons:code,docs:left-buttons:stars:right); the Card Builder carried them through but had no way to edit them. It does now, with menus and by dragging.

• Groups row (comes up with the Buttons row, or show all): one line per other group — its buttons in order (< >, a ✕ on an empty room, + empty), its area (LHS, center, RHS, bottom, or a strip at the top), up and down and across, buttons per row, and ✕ group to put its buttons back in the first group.
• → menu on every button, in the first group's order line and in a group's own line: send it to the first group, another, or new group (on the side away from the buttons first). The paper button and the parts among the buttons stay in the first group, so they have no menu.
• Drag in the preview: a button dragged onto a button of its own group reorders; onto a button of another group it joins that group there; onto an area it joins the group that has the area, or makes a new one; the area zones are outlined while dragging. A group left with no button is gone.
• Unticking a button's pill hides it wherever it is. A key is in one group, always; all in the first group is all but what other groups have.
• regroup, claimed, mainLinks, newGroup in model.js are pure and tested (27 new tests: moves along, out, in, new group, the paper button staying, nothing mutated, controls reading a name back, all in another group). The DOM side was checked in a browser by driving it: menu → new group, area/up and down/rows, back; and dragging docs onto stars, stars onto docs, docs back onto code, code to the bottom edge, each giving the expected name.
• data-g on each list so the preview knows its group; cardFace's groups carry their number.
• Docs in AGENTS.md; the recording of Chrome's layout is stamped again (its layouts are identical).

Screenshots

unxt. Sending stars to a new group from its → menu; the Groups row appears, the preview shows the group:

Its area set to the left and its up and down to the bottom — the stars at the foot of the left side, the other buttons on the right:

After dragging in the preview (docs onto stars, stars onto docs, docs back onto code, code to the bottom edge) — buttons:paper,docs:right-buttons:stars:left-buttons:code:bottom:

• npm run test:schema passes; 701 unit tests and the build pass

🤖 Generated with Claude Code

[github-actions]

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