feat(admin): refine header layout and logo placement

- Left-align logo across breakpoints; remove duplicate centered/mobile blocks
- Add date separator and spacing; keep header compact and readable

fix(admin): prevent category badge overlap in grid

- Move badge to top-left; make non-interactive; constrain width to avoid checkbox collisions

chore(docker): support ADMIN_PASSWORD in docker-compose

- Allow setting initial admin password via env for easier provisioning

chore(backend): normalize EOF newline in set-admin-password.js

Refs: admin-header-layout, category-badge-overlap, docker-admin-password

frontend/src/components/admin/AdminPhotoGrid.tsx

@@ -248,10 +248,10 @@ export const AdminPhotoGrid: React.FC<AdminPhotoGridProps> = ({
               </div>
             </div>
 
-            {/* Category Badge */}
+            {/* Category Badge - move to top-left and prevent overlap with select checkbox */}
             {photo.category_name && (
-              <div className="absolute right-2" style={{ top: (selectedPhotos.has(photo.id) || isSelectionMode) ? '40px' : '8px' }}>
-                <span className="px-2 py-1 text-xs font-medium bg-white/90 text-neutral-700 rounded">
+              <div className="absolute left-2 top-2 pointer-events-none">
+                <span className="px-2 py-1 text-xs font-medium bg-white/90 text-neutral-700 rounded max-w-[70%] whitespace-nowrap overflow-hidden text-ellipsis">
                   {photo.category_name}
                 </span>
               </div>