Build menu: hover popup with full info, top-left card hidden while building

The short description row became a status row for the selected piece
(variant, Replace, ghosts, messages). Gamepad shows the selected tile's popup.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

docs/agent-log.md

@@ -4,6 +4,27 @@ What agents have done, newest first. Add an entry for every piece of work: the d
 note or request it was for, what changed, the files touched, the tests run, and anything left
 open or not verified. Keep each entry short; the git history has the details.
 
+## 2026-10-23: build menu hover popup, top-left card hidden while building (Claude Code, with Codex)
+
+Notes: "mouse hover reviels a new info popup…" and "dont need the short description in the build
+menu…". The owner chose to hide the top-left card entirely while building.
+
+- `src/ui/build-menu.js`: `#bb-pop` above the hovered tile (icon, name, cost, size, power, full
+  description, how to place, filter help, build keys), clamped to the window; on a gamepad it
+  shows for the selected tile. The `.bb-tip` row became `.bb-status`: variant (material,
+  direction, filter) chips, Replace · Ctrl, ghosts waiting, and status messages. The bar now
+  updates its parts separately so hovering doesn't rebuild the tiles.
+- `src/ui/selection.js`: `#selcard` is hidden for the build tool unless copying, cutting or
+  pasting; the build branch moved to the bar. `src/styles/style.css`: popup and status styles;
+  on narrow screens the bottom-right panel moves up while building.
+- `src/ui/notebook.js`, `docs/DESIGN.md`, `docs/PROJECT_MAP.md`.
+- Tests: `play.py` 118 checks (popup on hover, switching tiles, hidden on leave, gamepad,
+  no `.bb-tip`, card hidden while building and back for tools 1 and 2, status in the bar; the
+  Ctrl replace check now reads the bar). All 11 headless suites pass. `t_smooth.py`'s
+  half-resolution check is still flaky under load (~4.8): 1 pass in 3 runs, as before.
+- Screenshots in `shots/` (build-popup-*) at 1280×800 and 900×700 in both looks.
+- Open: at 900px wide the bottom-left hover-info panel sits partly under the build bar.
+
 ## 2026-10-23: a backed-up heap on a belt no longer shears (Claude Code, with Codex)
 
 Note: "belts with a big pile on top only move the grains on the top of the stack…". The owner's