style(design): every remaining surface joins the shell palette

The audit found the workspace clean but eleven other surfaces still painted from the
old family. Measured before, per surface (unsanctioned chromatic / cool neutrals /
off-scale radii): 源码 174/28/5, 设置·提供方 8/47/13, 设置·外观 21/46/20, 通知 7/14/11,
统计 32/78/11, 模板 0/34/11. After: 0/0/2 everywhere (the two are the hidden file
input inside the shadcn Input).

Three alias layers were the root, not thirty components:

- the --cad-* layer now resolves to the shell tokens instead of a second cool palette;
- shadcn's base tokens (--background, --foreground, --card, --popover, --primary,
  --muted, --accent, --border, --input) do the same, so every primitive inherits the
  shell surface and text;
- the radius steps are pinned to 3/4/6/9 instead of shadcn's 6/8/10/14 derivation.

Then the files that were hardcoded rather than token-driven:

- 状态色 (types.tsx) and the state hexes used by the strip and stats move to
  pass/warn/fail; the activity feed and notification maps lose their lime/rose/amber;
  part-family icons stop painting a hue per family (section 11 forbids that rainbow);
- the SCAD editor's syntax map loses its seven hues for role-based tokens (one accent
  for keywords, caution for engine variables, the text ladder for the rest);
- 模板 cards and 案例记忆 are re-tokenised and re-copied to Chinese;
- the 外观 panel is rebuilt as an honest control: it offered accent hues, font size,
  density and an animation switch, none of which had a consumer left, and its accent
  wrote --cad-accent/--primary/--ring - a second palette writer that fought the shell.
  It now offers the three theme modes that actually work, plus one line saying the
  palette is fixed and density lives in the 面板 module.