feat(builder): FORMS package -- field editor, functional Subscribe/Search, box-model+anim rollout

- FormStylePanel: ContactForm field editor (add/remove/reorder via
  ArrayPropEditor + manual move up/down) covering label/name/placeholder/
  type (full sanitizeInputType allowlist + textarea/select)/required/
  options.
- SubscribeForm.toHtml: was a dead `<form method="POST">` with no action at
  all -- wired through the same relayFormWiring contract as ContactForm/
  FormContainer so a recipientEmail makes it actually submit (marker +
  placeholder action + honeypot), falling back to action="#" otherwise.
- SearchBar: was purely decorative (no action/method/input name) -- now a
  real GET form (configurable target, default "/") with input name="q",
  safeUrl-guarded against javascript:/vbscript: breakout.
- Box-model (margin/padding per-side, border, shadow, opacity), entrance
  animation, and hide-on-device controls added to FormStylePanel and
  rolled out (blank/false craft.props defaults) across ContactForm,
  FormContainer, InputField, TextareaField, FormButton, SubscribeForm,
  SearchBar. No toHtml changes needed for animation/visibility --
  html-export.ts's buildDataAttrs() already emits data-animation/
  data-hide-* generically from these prop names.
- Extended toHtml tests for all 7 components: field-type rendering
  (incl. textarea/select), type-attribute XSS sanitization, relay/GET
  functional wiring, box-model style passthrough, craft.props defaults.

npx vitest run: 689/689 passed. npm run build: green.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

craft/src/components/forms/FormContainer.tsx

@@ -12,6 +12,11 @@ interface FormContainerProps {
   thankYouUrl?: string;
   style?: CSSProperties;
   children?: React.ReactNode;
+  animation?: string;
+  animationDelay?: string;
+  hideOnDesktop?: boolean;
+  hideOnTablet?: boolean;
+  hideOnMobile?: boolean;
 }
 
 export const FormContainer: UserComponent<FormContainerProps> = ({
@@ -59,6 +64,11 @@ FormContainer.craft = {
       borderRadius: '8px',
       border: '1px solid #e4e4e7',
     },
+    animation: '',
+    animationDelay: '',
+    hideOnDesktop: false,
+    hideOnTablet: false,
+    hideOnMobile: false,
   },
   rules: {
     canDrag: () => true,