fix: stop dimming setup card bodies

Clack's `p.note` defaults to `format: e => styleText("dim", e)`, which
fades note bodies regardless of the project's stated readability stance
(see comment on `dimWrap` in setup/lib/theme.ts: "prose renders at the
terminal's regular weight"). The dim styling makes body copy hard to
read on dark terminals and visibly washes out brand-colored segments
embedded in cards (e.g. the chip + bold heading rows).

Add a `note()` helper in setup/lib/theme.ts that wraps `p.note` with a
pass-through formatter, and route every setup-flow `p.note` call site
through it: setup/auto.ts, every setup/channels/*.ts adapter, and the
two setup/lib/claude-* helpers.

Pre-styled segments (brandBold, brandChip, formatPairingCard,
formatCodeCard) now render at full strength instead of being faded
alongside surrounding prose.

setup/lib/theme.ts

@@ -11,6 +11,7 @@
  *   - COLORTERM truecolor/24bit  → 24-bit ANSI (exact brand cyan)
  *   - Otherwise                  → kleur's 16-color cyan (closest fallback)
  */
+import * as p from '@clack/prompts';
 import k from 'kleur';
 
 const USE_ANSI = Boolean(process.stdout.isTTY) && !process.env.NO_COLOR;
@@ -68,6 +69,19 @@ export function dimWrap(text: string, gutter: number): string {
   return wrapForGutter(text, gutter);
 }
 
+/**
+ * Wrap clack's `p.note` with the dim formatter disabled. By default
+ * clack renders note bodies through `styleText("dim", …)`, which the
+ * project's prose-readability stance (see `dimWrap` above) explicitly
+ * rejects. Pass-through formatter keeps body text at the terminal's
+ * regular weight; pre-styled segments (chips, bold, brand color) come
+ * through unfaded.
+ */
+const passthroughFormat = (s: string): string => s;
+export function note(message: string, title?: string): void {
+  p.note(message, title, { format: passthroughFormat });
+}
+
 const ANSI_RE = /\x1b\[[0-9;]*m/g;
 
 function visibleLength(s: string): number {