SKILL.md polish pass (Paul's seven notes)

- Setup 1 collapsed to run-and-follow; NO_PRODUCT_MD divert logic incl.
  unattended exception moved into context.mjs directive (no circular ref)
- Modes moved before Craft floor; Registers heading renamed Modes
- frontend-design near-verbatims removed (structural-devices rule,
  CSS-specificity example); copy rule rewritten in own voice
- Craft floor: dropped prefers-reduced-motion (a11y lives in polish/
  harden/audit) and edit-source clause; heading space-above folded
  into spacing rhythm
- Mode descriptions de-biased: surface-role definitions, no niche
  lists; Read rewritten (comprehension earned twice), density claims
  removed from Read and Operate
- craft/teach deprecation reduced to routing facts; codex illustration
  line reworded; codex tells flagged for gpt-5.6 revalidation

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

skill/scripts/context.mjs

@@ -899,11 +899,14 @@ async function cli() {
     // — cheap models miss the empty case more often than the explicit one.
     const parts = [
       'NO_PRODUCT_MD: This project has no PRODUCT.md yet. ' +
-      'Follow SKILL.md Setup step 1: for `init`, `teach`, `craft`, `shape`, ' +
+      'For `init`, `teach`, `craft`, `shape`, ' +
       'or wording that clearly maps to a from-scratch build/shape flow, load ' +
-      'reference/init.md and write PRODUCT.md first; for any other (scoped) ' +
-      'command against existing code, proceed using the code as context and ' +
-      `offer \`${IMPECCABLE_COMMAND} init\` as a suggestion (do not block).`,
+      'reference/init.md and write PRODUCT.md first, unless no user can ' +
+      'respond (a one-shot or automated run, or the user said not to ask): ' +
+      'then write a one-paragraph understanding of the product, audience, ' +
+      'and the page\'s job from the brief, and continue. For any other ' +
+      '(scoped) command against existing code, proceed using the code as ' +
+      `context and offer \`${IMPECCABLE_COMMAND} init\` as a suggestion (do not block).`,
       'NEW_WORK: No committed design context was found. If this task produces ' +
       'new design (a build from scratch, or a redesign that discards the ' +
       'current look), you MUST read reference/new-work.md before making any ' +