fix(frontend): shared mark on its own line in trash rows, undo ignores the trailing click, trash segment has a key

frontend/src/lib/components/disk/StoragePanel.svelte

@@ -37,6 +37,7 @@
 
   const PAGE = 30;
   const UNDO_MS = 12_000;
+  const UNDO_GUARD_MS = 600;
 
   let summary = $state<StorageSummary | null>(null);
   let files = $state<StorageFile[]>([]);
@@ -54,6 +55,7 @@
   const selected = new SvelteSet<number>();
   let token = 0;
   let undoTimer: ReturnType<typeof setTimeout> | undefined;
+  let undoShownAt = 0;
 
   const heaviest = $derived(files[0]?.file_size ?? 0);
   const chosen = $derived(files.filter((file) => selected.has(file.media_id)));
@@ -151,6 +153,7 @@
     hideUndo();
     if (outcome.files > 0) {
       undo = { files: trashed, outcome };
+      undoShownAt = Date.now();
       undoTimer = setTimeout(hideUndo, UNDO_MS);
     }
   }
@@ -185,7 +188,7 @@
   }
 
   async function restoreLast() {
-    if (undo === null) {
+    if (undo === null || Date.now() - undoShownAt < UNDO_GUARD_MS) {
       return;
     }
     const restored = undo;
@@ -290,9 +293,13 @@
       <Icon name="delete" size="1.375rem" />
       <span class="label">Корзина</span>
       <span class="value">
-        {summary.trash_files > 0
-          ? `${filesLabel(summary.trash_files)} · ${formatBytes(summary.trash_bytes)}`
-          : "пусто"}
+        {#if summary.trash_files > 0}
+          <span class="swatch"></span>
+          {filesLabel(summary.trash_files)}
+          · {formatBytes(summary.trash_bytes)}
+        {:else}
+          пусто
+        {/if}
       </span>
       <Icon name="next" size="1.125rem" />
     </button>
@@ -581,10 +588,21 @@
     }
 
     .value {
+      display: flex;
+      gap: 0.375rem;
+      align-items: center;
+
       font-size: 0.8125rem;
       font-variant-numeric: tabular-nums;
     }
 
+    .swatch {
+      width: 0.5rem;
+      height: 0.5rem;
+      border-radius: 50%;
+      background-color: rgba(var(--color-text-secondary-rgb), 0.35);
+    }
+
     &:focus-visible {
       outline: 2px solid var(--color-primary);
       outline-offset: -2px;