feat: image compress before upload

lib/source-reference.ts

@@ -351,6 +351,37 @@ export function referenceFromUrl(
   return { title: bookName, detail: null };
 }
 
+/**
+ * Resolve a post's source into structured `{ title, detail }` for
+ * multi-line share/copy payloads. Mirrors the formatCopyText pattern
+ * from selection-toolbar/shared.tsx so Send + Copy produce the same
+ * citation block.
+ *
+ * Two routes to the structured shape:
+ *
+ *   1. Book URLs   → `referenceFromUrl` parses the path.
+ *   2. Anything else (letters, essays, transcriptions, magazines):
+ *      `source_title` was composed by compose-post.tsx as
+ *      "Title — Detail" using ` — ` as the join. Split on the first
+ *      occurrence to recover the structured fields.
+ *
+ * Falls back to title-only with no detail when no separator is present.
+ */
+export function structuredReferenceForPost(
+  sourceUrl: string,
+  sourceTitle: string | null | undefined,
+): { title: string; detail: string | null } {
+  const r = referenceFromUrl(sourceUrl);
+  if (r) return r;
+  const stored = sourceTitle?.trim() || "Source";
+  const idx = stored.indexOf(" — ");
+  if (idx === -1) return { title: stored, detail: null };
+  return {
+    title: stored.slice(0, idx).trim(),
+    detail: stored.slice(idx + 3).trim() || null,
+  };
+}
+
 /**
  * Render a one-line citation string for a post/bookmark card.
  *