fix(mdviewer): preserve scroll position when closing image edit dialog

Place cursor near the image on dialog close so selection handlers don't
scroll to top. Use requestAnimationFrame to restore scroll position
after any async handlers that fire from the focus/selection change.

Author: abose

src-mdviewer/src/components/image-popover.js

@@ -223,9 +223,30 @@ function showEditDialog(imgEl, currentSrc, currentAlt) {
     urlInput.select();
 
     function close() {
+        const appViewer = document.getElementById("app-viewer");
+        const scrollTop = appViewer ? appViewer.scrollTop : 0;
         backdrop.remove();
-        if (contentEl) {
+        // Place cursor near the image so focus doesn't reset to top
+        if (imgEl && imgEl.parentNode && contentEl) {
+            const block = imgEl.closest("p, div, li") || imgEl.parentNode;
+            const range = document.createRange();
+            if (block.nextSibling) {
+                range.setStartBefore(block.nextSibling);
+            } else {
+                range.selectNodeContents(block);
+                range.collapse(false);
+            }
+            const sel = window.getSelection();
+            sel.removeAllRanges();
+            sel.addRange(range);
             contentEl.focus({ preventScroll: true });
+        } else if (contentEl) {
+            contentEl.focus({ preventScroll: true });
+        }
+        // Restore scroll in case async handlers shifted it
+        if (appViewer) {
+            appViewer.scrollTop = scrollTop;
+            requestAnimationFrame(() => { appViewer.scrollTop = scrollTop; });
         }
     }