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/media/MapEmbed.toHtml.test.ts

@@ -27,3 +27,41 @@ describe('MapEmbed.toHtml iframe src ampersand encoding (F-export review Minor)'
     expect(srcMatch![1]).not.toMatch(/&(?!amp;)/);
   });
 });
+
+describe('MapEmbed.toHtml address/zoom/height XSS hardening', () => {
+  test('a malicious address cannot break out of the src or title attribute', () => {
+    const malicious = 'X" onerror="alert(1)';
+    const { html } = toHtml({ address: malicious }, '');
+    expect(html).not.toContain('onerror="alert(1)"');
+  });
+
+  test('a wrong-typed zoom (string with attribute-breakout chars) cannot break out of the src attribute', () => {
+    const malicious = '14"><script>alert(1)</script>' as any;
+    const { html } = toHtml({ address: 'X', zoom: malicious }, '');
+    expect(html).not.toContain('<script>alert(1)</script>');
+    expect(html).not.toContain('"><script');
+  });
+
+  test('a wrong-typed zoom is coerced to a safe numeric value in the exported URL (defense in depth beyond escaping)', () => {
+    const malicious = '14"><script>alert(1)</script>' as any;
+    const { html } = toHtml({ address: 'X', zoom: malicious }, '');
+    const srcMatch = html.match(/<iframe src="([^"]+)"/);
+    expect(srcMatch).toBeTruthy();
+    // Decode the entity-escaped src back to a plain string and confirm the
+    // `z=` param is a bare, well-formed number -- not the raw attacker string.
+    const decoded = srcMatch![1].replace(/&amp;/g, '&').replace(/&quot;/g, '"').replace(/&lt;/g, '<').replace(/&gt;/g, '>');
+    expect(decoded).toMatch(/[&?]z=\d+(&|$)/);
+  });
+
+  test('a malicious height cannot break out of the iframe style attribute', () => {
+    const malicious = '400px" onmouseover="alert(1)';
+    const { html } = toHtml({ address: 'X', height: malicious }, '');
+    expect(html).not.toContain('onmouseover="alert(1)"');
+  });
+
+  test('a normal zoom/height still renders correctly', () => {
+    const { html } = toHtml({ address: 'X', zoom: 10, height: '300px' }, '');
+    expect(html).toContain('z=10');
+    expect(html).toContain('height:300px');
+  });
+});