fix(builder): escape/allowlist all attribute-value sinks incl. numeric/enum props (XSS)

An adversarial pass found 5 Critical XSS sinks where props declared number/enum
in TypeScript were interpolated raw into exported HTML attribute values,
trusting the type — but nothing enforces it at runtime (AI update_props only
validates node_id; deserialized saved state is untyped JSON). Fixed all 5
(NumberCounter data-target, StarRating aria-label, FormContainer method,
ContactForm/InputField input type) plus 6 sibling sinks found by an exhaustive
audit of every attribute-value interpolation across src/components: a
JS-source injection into ContentSlider's inline setInterval script, a
prototype-pollution-adjacent allowlist gap in Section's divider-shape lookup,
TextareaField rows, Testimonials rating aria-label, HeroSimple textAlign, and
MapEmbed zoom. Adds shared sanitizeFormMethod/sanitizeInputType allowlist
helpers to utils/escape.ts alongside the existing escapeAttr/safeUrl/cssValue
primitives. Every fix is TDD'd: a malicious-value test reproduces the raw
injection against the pre-fix code, then passes after the fix.

502 tests green (npx vitest run), tsc + vite build green (npm run build).

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

craft/src/components/sections/NumberCounter.toHtml.test.ts

@@ -47,3 +47,29 @@ describe('NumberCounter.toHtml deterministic + unique scope ids (thread node id,
     expect(wrapId1).not.toBe(wrapId2);
   });
 });
+
+describe('NumberCounter.toHtml counter.number is NOT runtime-type-checked -- must be sanitized before it reaches data-target', () => {
+  test('a malicious counter.number cannot break out of the data-target attribute to inject a <script> tag', () => {
+    const malicious = [
+      { number: '150"><script>alert(1)</script>', suffix: '+', label: 'Evil' },
+    ];
+    const { html } = toHtml({ counters: malicious }, '', 'node-nc-evil1');
+    expect(html).not.toContain('<script>alert(1)</script>');
+    expect(html).not.toContain('"><script>');
+  });
+
+  test('a malicious counter.number cannot break out of the data-target attribute to inject an onmouseover handler', () => {
+    const malicious = [
+      { number: '150" onmouseover="alert(1)', suffix: '+', label: 'Evil' },
+    ];
+    const { html } = toHtml({ counters: malicious }, '', 'node-nc-evil2');
+    expect(html).not.toContain('onmouseover=');
+    expect(html).not.toMatch(/data-target="150" onmouseover/);
+  });
+
+  test('normal numeric counter.number values still render as data-target="150"', () => {
+    const normal = [{ number: 150, suffix: '+', label: 'Projects' }];
+    const { html } = toHtml({ counters: normal }, '', 'node-nc-normal');
+    expect(html).toContain('data-target="150"');
+  });
+});