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/ContentSlider.toHtml.test.ts

@@ -110,3 +110,23 @@ describe('ContentSlider.toHtml renders slide.imageSrc as a background-image (INT
     expect(html).toContain('background-color:#123456');
   });
 });
+
+describe('ContentSlider.toHtml interval is NOT runtime-type-checked -- must be coerced before it reaches the inline <script> numeric context', () => {
+  test('a malicious interval string cannot inject arbitrary JS into the autoplay setInterval call', () => {
+    const malicious = '5000);alert(document.domain);//';
+    const { html } = toHtml({ slides, autoplay: true, interval: malicious }, '');
+    expect(html).not.toContain('alert(document.domain)');
+    // the setInterval call must still be well-formed with a plain numeral delay
+    expect(html).toMatch(/setInterval\(function\(\)\{show\(current\+1\);\},\d+\);/);
+  });
+
+  test('a non-numeric interval falls back to a safe default delay', () => {
+    const { html } = toHtml({ slides, autoplay: true, interval: 'not-a-number' }, '');
+    expect(html).toMatch(/setInterval\(function\(\)\{show\(current\+1\);\},5000\);/);
+  });
+
+  test('a normal numeric interval still renders as the exact configured delay', () => {
+    const { html } = toHtml({ slides, autoplay: true, interval: 3000 }, '');
+    expect(html).toMatch(/setInterval\(function\(\)\{show\(current\+1\);\},3000\);/);
+  });
+});