feat(story-blocks): add full-bleed and image-caption shortcodes

Two new shortcodes for immersive storytelling:
- [full-bleed image="" caption="" credit=""] — viewport-wide image, max 80vh
- [image-caption image="" caption="" credit="" width="column|full|bleed"] — photo at configurable width with caption

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01WPJztrVGbwic2xTG7G9fjM

themes/intotheeast/css/style.css

@@ -1647,6 +1647,65 @@ body::after {
 }
 .pgallery__dot.is-active { background: var(--color-accent); }
 
+/* ── FullBleed shortcode ──────────────────────────────────── */
+.full-bleed {
+    width: 100vw;
+    left: 50%;
+    margin-left: -50vw;
+    position: relative;
+    margin-top: var(--space-16);
+    margin-bottom: var(--space-16);
+}
+.full-bleed__img {
+    width: 100%;
+    display: block;
+    max-height: 80vh;
+    object-fit: cover;
+}
+.full-bleed__caption {
+    text-align: center;
+    font-family: var(--font-ui);
+    font-size: var(--text-sm);
+    color: var(--color-ink-muted);
+    margin-top: var(--space-3);
+    padding: 0 var(--space-8);
+}
+.full-bleed__credit { font-style: italic; }
+
+/* ── ImageCaption shortcode ───────────────────────────────── */
+.img-caption {
+    margin-top: var(--space-12);
+    margin-bottom: var(--space-12);
+}
+.img-caption__img {
+    width: 100%;
+    display: block;
+    border-radius: var(--radius-sm);
+}
+.img-caption__text {
+    font-family: var(--font-ui);
+    font-size: var(--text-sm);
+    color: var(--color-ink-muted);
+    margin-top: var(--space-3);
+}
+.img-caption__credit { font-style: italic; }
+.img-caption--full {
+    width: calc(100% + var(--space-16));
+    margin-left: calc(var(--space-8) * -1);
+}
+.img-caption--full .img-caption__img { border-radius: 0; }
+.img-caption--bleed {
+    width: 100vw;
+    left: 50%;
+    margin-left: -50vw;
+    position: relative;
+}
+.img-caption--bleed .img-caption__img {
+    border-radius: 0;
+    max-height: 80vh;
+    object-fit: cover;
+}
+
 /* ── Stories listing ──────────────────────────────────────── */
 .stories-listing { padding: var(--space-10) 0; }
 .stories-listing__heading {