Merge branch 'feat/outliner-polish' into dev

Offer /number at start or end like the other block commands and start a
numbered list when typing "1. " into an empty bullet.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

frontend/src/index.css

@@ -318,12 +318,14 @@ body {
     pointer-events: none;
   }
   .count-badge-accent {
-    background-color: var(--accent-primary);
-    color: var(--text-on-accent);
+    background: var(--accent-dim);
+    color: var(--accent-primary);
+    border: 1px solid var(--accent-border);
   }
   .count-badge-muted {
-    background-color: var(--text-muted);
-    color: var(--bg-panel);
+    background-color: var(--bg-panel-elevated);
+    color: var(--text-muted);
+    border: 1px solid var(--border-color);
   }
   .count-badge-corner {
     position: absolute;