docs(plan): M4-b — the creation screen, seven tasks

TDD task-by-task: NewGame's public seeded roll -> the eleven fragments ->
CreationCopy -> CreationDraft -> the theme -> the scene -> the docs.

Both of traps.md's bugs get a named guard rather than a hope: the pipeline test
that asserts what the screen SHOWED is what construct BUILT (and a step that
re-breaks the code to prove the test can fail), and a no-default-parameters rule
on the two new public functions.

Also corrects the spec: PrimaryCTA already has a disabled stylebox.

docs/superpowers/specs/2026-07-13-character-creation-ui-design.md

@@ -171,9 +171,12 @@ the Cutpurse's d8, the card follows — because the card never knew the number.
 
 **Theme additions.** A skill chip has three states — unpicked, picked, and *granted by your
 race so it cannot be picked* — which is a `Button` in `toggle_mode` needing
-`normal`/`pressed`/`disabled` styleboxes. `Chip` was built for one state, and `PrimaryCTA`
-has no `disabled`. Both are extended in **`build_game_theme.gd`** and the `.tres`
-**regenerated** — never hand-edited, no hex in a scene or script (the M3-a rule).
+`normal`/`pressed`/`disabled` styleboxes. The existing `Chip` is a display badge with no
+`disabled` and no selected look, and the race/calling cards need a "chosen" crimson-ring
+state that nothing in the theme has. (`PrimaryCTA` **already** carries `disabled` +
+`font_disabled_color` — the CTA needs nothing new.) The new variations are added to
+**`build_game_theme.gd`** + `theme_keys.gd` and the `.tres` **regenerated** — never
+hand-edited, no hex in a scene or script (the M3-a rule).
 
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