Fix multi-image upload in article editor; add thumbnail lightbox

- All selected images now upload and insert correctly (was: only last
  image kept due to stale content closure in loop)
- Images inserted as a block with proper newline padding
- Thumbnail strip thumbnails are now clickable — opens a lightbox;
  click overlay to dismiss

src/components/article/ArticleEditor.tsx

@@ -54,6 +54,7 @@ export function ArticleEditor() {
   const [zenMode, setZenMode] = useState(false);
   const [zenHint, setZenHint] = useState(false);
   const zenTextareaRef = useRef<HTMLTextAreaElement>(null);
+  const [lightboxUrl, setLightboxUrl] = useState<string | null>(null);
 
   const toggleZen = useCallback(async () => {
     const win = getCurrentWindow();
@@ -426,11 +427,11 @@ export function ArticleEditor() {
           <div className="flex items-center gap-2 px-6 py-2 border-b border-border bg-bg-raised/50 overflow-x-auto shrink-0">
             <span className="text-text-dim text-[10px] shrink-0">{inlineImages.length} {inlineImages.length === 1 ? "image" : "images"}</span>
             {inlineImages.map((img, i) => (
-              <div key={i} className="relative shrink-0 group">
+              <div key={i} className="relative shrink-0 group cursor-zoom-in" onClick={() => setLightboxUrl(img.url)}>
                 <img
                   src={img.url}
                   alt={img.alt}
-                  className="h-12 w-auto rounded-sm border border-border object-cover"
+                  className="h-12 w-auto rounded-sm border border-border object-cover group-hover:border-accent transition-colors"
                   onError={(e) => { (e.target as HTMLImageElement).style.display = "none"; }}
                 />
               </div>
@@ -438,6 +439,20 @@ export function ArticleEditor() {
           </div>
         )}
 
+        {/* Lightbox */}
+        {lightboxUrl && (
+          <div
+            className="fixed inset-0 z-50 bg-black/80 flex items-center justify-center cursor-zoom-out"
+            onClick={() => setLightboxUrl(null)}
+          >
+            <img
+              src={lightboxUrl}
+              className="max-w-[90vw] max-h-[90vh] rounded-md shadow-2xl object-contain"
+              onClick={(e) => e.stopPropagation()}
+            />
+          </div>
+        )}
+
         {/* Content area */}
         <div className="flex-1 overflow-y-auto px-6 pb-6">
           {mode === "write" ? (

src/components/article/MarkdownToolbar.tsx

@@ -151,19 +151,24 @@ export function MarkdownToolbar({ textareaRef, content, setContent, setUploading
       setUploading?.(true);
       setError?.(null);
       try {
+        const mimeMap: Record<string, string> = {
+          jpg: "image/jpeg", jpeg: "image/jpeg", png: "image/png", gif: "image/gif",
+          webp: "image/webp", svg: "image/svg+xml",
+        };
+        const snippets: string[] = [];
         for (const filePath of paths) {
           const bytes = await readFile(filePath);
           const fileName = filePath.split(/[\\/]/).pop() || "image.png";
           const ext = fileName.split(".").pop()?.toLowerCase() || "png";
-          const mimeMap: Record<string, string> = {
-            jpg: "image/jpeg", jpeg: "image/jpeg", png: "image/png", gif: "image/gif",
-            webp: "image/webp", svg: "image/svg+xml",
-          };
           const url = await uploadBytes(new Uint8Array(bytes), fileName, mimeMap[ext] || "image/png");
-          const textarea = textareaRef.current;
-          if (textarea) {
-            applyMarkdown(textarea, "image", content, setContent, `![${fileName}](${url})`);
-          }
+          snippets.push(`![${fileName}](${url})`);
+        }
+        const textarea = textareaRef.current;
+        if (textarea && snippets.length > 0) {
+          const cursorPos = textarea.selectionStart ?? content.length;
+          const needsLeadingNewline = cursorPos > 0 && content[cursorPos - 1] !== "\n";
+          const block = (needsLeadingNewline ? "\n\n" : "") + snippets.join("\n\n") + "\n\n";
+          applyMarkdown(textarea, "image", content, setContent, block);
         }
       } finally {
         setUploading?.(false);