feat(builder): media package -- image crop/perf, video size+picker, gallery cols/lightbox, box-model+anim/vis rollout

- ImageBlock/ImageStylePanel: SizeControl width(absorbs old maxWidth
  presets)/height, AspectRatioControl + OBJECT_FIT grid + FocalPointGrid for
  CSS framing crop (aspect-ratio/object-fit/object-position on the <img>).
  Exported <img> always gets loading="lazy" decoding="async", plus width/
  height attrs when the style has a plain px length (pxAttr helper).
- VideoBlock/MediaStylePanel: Video URL text input replaced with
  AssetPicker(mediaType="video") writing videoUrl (paste-URL still handles
  YouTube/Vimeo, upload/browse handle files). Added SizeControl(width) +
  AspectRatioControl so the video frame honors real size/aspect instead of
  a hardcoded 16:9 (padding-bottom hack replaced with CSS aspect-ratio).
  New optional `poster` prop (image AssetPicker) + preload="metadata" on
  file-type <video>.
- Gallery: surfaced the existing-but-unexposed `columns` and `lightbox`
  props with panel controls.
- All 5 owned components (ImageBlock, VideoBlock, Gallery, ContentSlider,
  MapEmbed): added margin/padding (per-side)/border/box-shadow/opacity style
  defaults + AnimationControl/VisibilityControl-backed animation/
  animationDelay/hideOnDesktop/hideOnTablet/hideOnMobile props. New shared
  mediaBoxModel.tsx (package-local, not shared.tsx) DRYs the box-model +
  border/effects + animation/visibility panel sections across
  ImageStylePanel and MediaStylePanel.
- Tests: extended *.toHtml.test.ts for all 5 components (crop/perf attrs,
  video size/aspect/poster/preload, gallery columns/lightbox, box-model
  style emission, craft.props presence) + new MediaStylePanel.video.test.tsx
  verifying the AssetPicker wiring writes videoUrl/poster and the video-only
  size controls are gated on videoUrl. 694 tests green, tsc + vite build
  clean.

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

craft/src/components/media/VideoBlock.toHtml.test.ts

@@ -118,3 +118,75 @@ describe('VideoBlock.toHtml iframe src ampersand encoding (F-export review Minor
     expect(srcMatch![1]).not.toMatch(/&(?!amp;)/);
   });
 });
+
+describe('VideoBlock.toHtml size + aspect ratio (frame honors style props, not a hardcoded 16:9)', () => {
+  test('direct file: style.width flows to the wrapper, style.aspectRatio flows to the <video>', () => {
+    const { html } = toHtml({ videoUrl: 'https://example.com/clip.mp4', style: { width: '50%', aspectRatio: '4 / 3' } }, '');
+    expect(html).toMatch(/<div style="[^"]*width:50%[^"]*"/);
+    expect(html).toMatch(/<video[^>]*style="[^"]*aspect-ratio:4 \/ 3[^"]*"/);
+  });
+
+  test('direct file: no aspectRatio set -- no aspect-ratio declaration is forced onto the <video>', () => {
+    const { html } = toHtml({ videoUrl: 'https://example.com/clip.mp4' }, '');
+    const videoTag = html.match(/<video[^>]*>/)![0];
+    expect(videoTag).not.toContain('aspect-ratio');
+  });
+
+  test('YouTube/Vimeo: style.aspectRatio overrides the 16:9 default on the iframe container', () => {
+    const { html } = toHtml({ videoUrl: 'https://vimeo.com/123456789', style: { aspectRatio: '1 / 1' } }, '');
+    expect(html).toMatch(/<div[^>]*style="[^"]*aspect-ratio:1 \/ 1[^"]*"[^>]*><iframe/);
+  });
+
+  test('YouTube/Vimeo: defaults to 16 / 9 when no aspectRatio style is set', () => {
+    const { html } = toHtml({ videoUrl: 'https://vimeo.com/123456789' }, '');
+    expect(html).toMatch(/<div[^>]*style="[^"]*aspect-ratio:16 \/ 9[^"]*"[^>]*><iframe/);
+  });
+});
+
+describe('VideoBlock.toHtml poster + preload (file type)', () => {
+  test('poster attribute is emitted (escaped) and preload="metadata" is always present on a direct file', () => {
+    const { html } = toHtml({ videoUrl: 'https://example.com/clip.mp4', poster: 'https://example.com/poster.jpg' }, '');
+    expect(html).toContain('poster="https://example.com/poster.jpg"');
+    expect(html).toContain('preload="metadata"');
+  });
+
+  test('no poster prop -- no poster attribute is emitted, but preload="metadata" still is', () => {
+    const { html } = toHtml({ videoUrl: 'https://example.com/clip.mp4' }, '');
+    expect(html).not.toContain('poster=');
+    expect(html).toContain('preload="metadata"');
+  });
+
+  test('a malicious poster (javascript: scheme) is blocked by safeImageUrl', () => {
+    const { html } = toHtml({ videoUrl: 'https://example.com/clip.mp4', poster: 'javascript:alert(1)' }, '');
+    expect(html).not.toContain('javascript:');
+  });
+
+  test('a poster value cannot break out of the poster attribute', () => {
+    const malicious = 'https://example.com/x.jpg" onerror="alert(1)';
+    const { html } = toHtml({ videoUrl: 'https://example.com/clip.mp4', poster: malicious }, '');
+    expect(html).not.toContain('onerror="alert(1)"');
+  });
+});
+
+describe('VideoBlock.craft.props exposes the box-model/animation/visibility rollout', () => {
+  test('poster, animation, animationDelay, hideOnDesktop/Tablet/Mobile are present with blank/false defaults', () => {
+    const props = (VideoBlock as any).craft.props;
+    expect(props.poster).toBe('');
+    expect(props.animation).toBe('');
+    expect(props.animationDelay).toBe('0');
+    expect(props.hideOnDesktop).toBe(false);
+    expect(props.hideOnTablet).toBe(false);
+    expect(props.hideOnMobile).toBe(false);
+  });
+
+  test('style carries blank/default box-model + size/aspect keys', () => {
+    const style = (VideoBlock as any).craft.props.style;
+    expect(style).toHaveProperty('width');
+    expect(style).toHaveProperty('aspectRatio');
+    expect(style).toHaveProperty('marginTop');
+    expect(style).toHaveProperty('paddingTop');
+    expect(style.border).toBe('none');
+    expect(style.boxShadow).toBe('none');
+    expect(style.opacity).toBe('1');
+  });
+});