fix(ui/alerts): InboxPage polish — status colors, selected-scrub on delete, drop stale comment

- STATE_ITEMS gains color dots (text-muted/error/success) to match SEVERITY_ITEMS
- onDeleteOne removes the deleted id from the selection Set so a follow-up bulk
  action doesn't try to re-delete a tombstoned row
- drop stale comment block that described an alternative SilenceRulesForSelection
  implementation not matching the shipped code

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

ui/src/pages/Alerts/InboxPage.tsx

@@ -34,9 +34,9 @@ const SEVERITY_ITEMS: ButtonGroupItem[] = [
 ];
 
 const STATE_ITEMS: ButtonGroupItem[] = [
-  { value: 'PENDING',  label: 'Pending'  },
+  { value: 'PENDING',  label: 'Pending',  color: 'var(--text-muted)' },
-  { value: 'FIRING',   label: 'Firing'   },
+  { value: 'FIRING',   label: 'Firing',   color: 'var(--error)' },
-  { value: 'RESOLVED', label: 'Resolved' },
+  { value: 'RESOLVED', label: 'Resolved', color: 'var(--success)' },
 ];
 
 // ── Bulk silence helper ─────────────────────────────────────────────────────
@@ -90,12 +90,6 @@ function SilenceRulesForSelection({ selected, rows }: SilenceRulesForSelectionPr
 
   const handleCustom = () => navigate('/alerts/silences');
 
-  // Render ONE SilenceRuleMenu that uses the first ruleId as its anchor but
-  // overrides the click handlers to fire against all selected rule IDs.
-  // We use a Dropdown-equivalent by wiring SilenceRuleMenu with the first
-  // ruleId; for bulk we drive our own mutation loop above.
-  // Since SilenceRuleMenu is self-contained, we render a parallel Button set
-  // for the bulk path to keep it clean.
   return (
     <div style={{ display: 'flex', gap: 'var(--space-xs)' }}>
       {SILENCE_PRESETS.map(({ label, hours }) => (
@@ -200,6 +194,12 @@ export default function InboxPage() {
   const onDeleteOne = async (id: string) => {
     try {
       await del.mutateAsync(id);
+      setSelected((prev) => {
+        if (!prev.has(id)) return prev;
+        const next = new Set(prev);
+        next.delete(id);
+        return next;
+      });
       // No built-in action slot in DS toast — render Undo as a Button node
       const undoNode = (
         <Button