fix(ui): polish across routing, groups, inbounds, mobile sidebar

A bundle of small UI fixes that surfaced together while reviewing the
panel.

Routing rules — stale Edit after drag:
- Dragging a rule and then clicking its Edit button used to open the
  modal with the *previous* rule's content. Root cause: desktopColumns
  was memoized with [t, isMobile, rows.length] (rows.length doesn't
  change on reorder), so the cached render function kept handing AntD
  the openEdit closure that captured the pre-drag rules array. Fix is
  a rulesRef updated each render and read inside openEdit, so even the
  cached closure sees the live array.
- Mobile rule cards on the same page were hard to tell apart: bumped
  the inter-card gap, slightly stronger border, soft shadow, and a
  small centered divider line between adjacent cards.

Mobile drawer (dark / ultra):
- The AntD Menu inside the mobile drawer was rendering with its own
  darkItemBg (#15161a / #050507) while the drawer body used the
  lighter colorBgElevated, producing visible two-tone seams. Force
  the drawer-content / drawer-body to the same dark color that the
  desktop sider uses, and make the menus transparent so they inherit.

Row menus — visual grouping:
- Groups page row menu: moved Rename above the divider so the
  ordering reads safe → divider → destructive (Remove from group,
  Delete clients, Delete group only) instead of mixing the two
  groups.
- Inbounds page row menu: inserted a divider before delAllClients /
  delete so the destructive items sit visually separated from the
  earlier safe actions.

Dropdown affordances:
- Non-danger dropdown items had no perceivable hover state (default
  colorBgTextHover is too subtle, especially under the light theme).
  Apply the same primary-tint pattern the sider/drawer menu uses: 14%
  primary background and primary color on label + icon.
- ant-dropdown-menu-item-divider now uses var(--ant-color-border)
  (and an explicit rgba in dark) so the separator is actually visible
  in the light theme.

Clients toolbar — narrow-desktop wrap:
- Between 769px and 920px, the bulk-action bar (Attach / Detach /
  Add to group / Ungroup / more + Delete) wrapped to two rows with
  Delete stranded alone on the right. In that range, switch the
  toolbar buttons to icon-only, tighten gap to 6px and inline padding
  to 8px so everything stays on one line.

frontend/src/pages/xray/RoutingTab.css

@@ -99,7 +99,7 @@
 .rule-list {
   display: flex;
   flex-direction: column;
-  gap: 8px;
+  gap: 14px;
 }
 
 .rule-card {
@@ -109,11 +109,24 @@
   gap: 8px;
   padding: 10px 12px;
   background: var(--bg-card, #fff);
-  border: 1px solid var(--ant-color-border-secondary);
+  border: 1px solid var(--ant-color-border);
   border-radius: 8px;
+  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.06);
   transition: opacity 0.15s, box-shadow 0.15s;
 }
 
+.rule-list > .rule-card:not(:last-child)::after {
+  content: '';
+  position: absolute;
+  left: 50%;
+  bottom: -8px;
+  width: 32px;
+  height: 1px;
+  background: var(--ant-color-border);
+  transform: translateX(-50%);
+  opacity: 0.7;
+}
+
 .rule-card.row-dragging {
   opacity: 0.4;
 }

frontend/src/pages/xray/RoutingTab.tsx

@@ -88,6 +88,8 @@ export default function RoutingTab({
     () => (templateSettings?.routing?.rules || []) as RoutingRule[],
     [templateSettings?.routing?.rules],
   );
+  const rulesRef = useRef(rules);
+  rulesRef.current = rules;
 
   const rows: RuleRow[] = useMemo(
     () =>
@@ -171,7 +173,7 @@ export default function RoutingTab({
     setRuleModalOpen(true);
   }
   function openEdit(idx: number) {
-    setEditingRule(rules[idx]);
+    setEditingRule(rulesRef.current[idx]);
     setEditingIndex(idx);
     setRuleModalOpen(true);
   }