fix: comma-separate D-level profiles, map restart to blue in timeline

- D-level profile names now joined with commas instead of concatenated spans
- Gateway trend restart indicator changed from yellow to blue (red/orange/blue scheme)

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

frontend/src/pages/DashboardPage.tsx

@@ -35,7 +35,7 @@ const statusIcon = (s: string) => {
 const trendColor = (item: GatewayTrendItem): string => {
   if (item.heartbeat_timeouts > 0) return 'var(--red)'
   if (item.feishu_disconnects > 0) return 'var(--orange)'
-  if (item.restarts > 0) return 'var(--yellow)'
+  if (item.restarts > 0) return 'var(--blue)'
   return 'var(--green)'
 }
 
@@ -98,11 +98,9 @@ function HealthBarChart({
       {dist.d_profiles && dist.d_profiles.length > 0 && (
         <div className="mt-3 pt-3 border-t" style={{ borderColor: 'var(--border)' }}>
           <span className="text-[12px]" style={{ color: 'var(--text-dim)' }}>D 级 Profile: </span>
-          {dist.d_profiles.map((name) => (
-            <span key={name} className="inline-block text-[12px] px-2 py-0.5 mr-1 mb-1 rounded-[var(--radius-sm)]" style={{ background: 'var(--bg-hover)', color: 'var(--red)' }}>
-              {name}
-            </span>
-          ))}
+          <span className="inline-block text-[12px] px-2 py-0.5 rounded-[var(--radius-sm)]" style={{ background: 'var(--bg-hover)', color: 'var(--red)' }}>
+            {dist.d_profiles.join(', ')}
+          </span>
         </div>
       )}
     </div>
@@ -207,7 +205,7 @@ export default function DashboardPage() {
 
     return {
       time: hourLabel(item.hour),
-      type: item.heartbeat_timeouts > 0 ? 'red' : item.feishu_disconnects > 0 ? 'orange' : item.restarts > 0 ? 'orange' : 'green',
+      type: item.heartbeat_timeouts > 0 ? 'red' : item.feishu_disconnects > 0 ? 'orange' : item.restarts > 0 ? 'blue' : 'green',
       tooltip: tooltipText,
       color: trendColor(item),
     }
@@ -286,7 +284,7 @@ export default function DashboardPage() {
             <span><span style={{ color: 'var(--green)' }}>●</span> 正常</span>
             <span><span style={{ color: 'var(--red)' }}>●</span> 心跳超时</span>
             <span><span style={{ color: 'var(--orange)' }}>●</span> 飞书断连</span>
-            <span><span style={{ color: 'var(--yellow)' }}>●</span> 重启</span>
+            <span><span style={{ color: 'var(--blue)' }}>●</span> 重启</span>
           </div>
         </div>
       </div>