Add fleet groups, agent screenshots, deploy guards, and Crucible polish.

server/web/src/help/screenshotDownload.ts

@@ -0,0 +1,42 @@
+/** Strip whitespace and download a remote desktop capture as a JPEG file. */
+export function sanitizeScreenshotBase64(raw: string): string {
+  const trimmed = raw.trim().replace(/^\uFEFF/, '');
+  let best = '';
+  for (const part of trimmed.split(/\s+/)) {
+    const cleaned = part.replace(/[^A-Za-z0-9+/=]/g, '');
+    if (cleaned.length > best.length && cleaned.length >= 100) {
+      best = cleaned;
+    }
+  }
+  if (best.length >= 100) return best;
+  return trimmed.replace(/[^A-Za-z0-9+/=]/g, '');
+}
+
+export function downloadScreenshotFromBase64(
+  base64: string,
+  agentLabel: string
+): boolean {
+  const clean = sanitizeScreenshotBase64(base64);
+  if (clean.length < 100) return false;
+
+  const safeName = agentLabel.replace(/[^\w.-]+/g, '_').slice(0, 64) || 'agent';
+  const stamp = new Date().toISOString().replace(/[:.]/g, '-');
+  const blob = base64ToBlob(clean, 'image/jpeg');
+  const url = URL.createObjectURL(blob);
+  const a = document.createElement('a');
+  a.href = url;
+  a.download = `screenshot-${safeName}-${stamp}.jpg`;
+  a.rel = 'noopener';
+  document.body.appendChild(a);
+  a.click();
+  a.remove();
+  URL.revokeObjectURL(url);
+  return true;
+}
+
+function base64ToBlob(b64: string, mime: string): Blob {
+  const binary = atob(b64);
+  const bytes = new Uint8Array(binary.length);
+  for (let i = 0; i < binary.length; i++) bytes[i] = binary.charCodeAt(i);
+  return new Blob([bytes], { type: mime });
+}