refactor(sidebar): emphasize active-tab conversations via rail color and status icon

- Highlight the vertical rail on conversations open in tabs with a darker primary tint and bleed 1px at both ends to stay continuous across cards
- Add emphasized state to SidebarStatusIcon mirroring the rail, deepening color when the conversation is open in a tab
- Redesign done icon as outlined circle + check, unify all status icons to sidebar-primary with consistent 0.75rem size and sidebar-tinted backdrop so they mask the rail

src/components/conversations/sidebar-conversation-card.tsx

@@ -67,6 +67,7 @@ const STATUS_ICON_COLORS: Record<ConversationStatus, string> = {
 interface SidebarConversationCardProps {
   conversation: DbConversationSummary
   isSelected: boolean
+  isOpenInTab?: boolean
   timeLabel?: string
   onSelect: (id: number, agentType: string) => void
   onDoubleClick?: (id: number, agentType: string) => void
@@ -79,6 +80,7 @@ interface SidebarConversationCardProps {
 export const SidebarConversationCard = memo(function SidebarConversationCard({
   conversation,
   isSelected,
+  isOpenInTab = false,
   timeLabel,
   onSelect,
   onDoubleClick,
@@ -146,14 +148,18 @@ export const SidebarConversationCard = memo(function SidebarConversationCard({
             >
               <span
                 aria-hidden
-                className="pointer-events-none absolute top-0 bottom-0 rounded-[0.125rem] bg-sidebar-primary/15"
+                className={cn(
+                  "pointer-events-none absolute -top-px -bottom-px z-0",
+                  isOpenInTab
+                    ? "bg-sidebar-primary/85"
+                    : "bg-sidebar-primary/30"
+                )}
                 style={{
-                  left: "0.875rem",
+                  left: "calc(0.875rem - 0.5px)",
                   width: "1px",
-                  transform: "translateX(-50%)",
                 }}
               />
-              <SidebarStatusIcon status={beadStatus} />
+              <SidebarStatusIcon status={beadStatus} emphasized={isOpenInTab} />
 
               <span
                 className={cn(

src/components/conversations/sidebar-conversation-list.tsx

@@ -318,6 +318,16 @@ export function SidebarConversationList({
     }
   }, [tabs, activeTabId])
 
+  const openTabConversationKeys = useMemo(() => {
+    const set = new Set<string>()
+    for (const tab of tabs) {
+      if (tab.conversationId != null) {
+        set.add(`${tab.agentType}:${tab.conversationId}`)
+      }
+    }
+    return set
+  }, [tabs])
+
   const [importing, setImporting] = useState(false)
   const [folderExpanded, setFolderExpanded] = useState<Record<number, boolean>>(
     {}
@@ -814,6 +824,9 @@ export function SidebarConversationList({
                           selectedConversation?.agentType === conv.agent_type &&
                           selectedConversation?.id === conv.id
                         }
+                        isOpenInTab={openTabConversationKeys.has(
+                          `${conv.agent_type}:${conv.id}`
+                        )}
                         timeLabel={formatRelative(conv.updated_at)}
                         onSelect={handleSelect}
                         onDoubleClick={handleDoubleClick}

src/components/conversations/sidebar-status-icon.tsx

@@ -6,6 +6,7 @@ export type SidebarBeadStatus = "done" | "active" | "running" | "failed"
 
 interface SidebarStatusIconProps {
   status: SidebarBeadStatus
+  emphasized?: boolean
   className?: string
 }
 
@@ -21,15 +22,15 @@ function IconFrame({
   return (
     <div
       className={cn(
-        "pointer-events-none absolute top-1/2",
+        "pointer-events-none absolute top-1/2 z-10",
-        "flex items-center justify-center",
+        "flex items-center justify-center rounded-full bg-sidebar",
         colorClass,
         className
       )}
       style={{
         left: "0.875rem",
-        width: "0.625rem",
+        width: "0.75rem",
-        height: "0.625rem",
+        height: "0.75rem",
         transform: "translate(-50%, -50%)",
       }}
       aria-hidden
@@ -41,34 +42,37 @@ function IconFrame({
 
 export function SidebarStatusIcon({
   status,
+  emphasized = false,
   className,
 }: SidebarStatusIconProps) {
   if (status === "running") {
     return (
       <IconFrame
-        colorClass="text-amber-600 dark:text-amber-400"
+        colorClass={
+          emphasized ? "text-sidebar-primary" : "text-sidebar-primary/65"
+        }
         className={className}
       >
         <svg
-          width="0.625rem"
+          width="0.75rem"
-          height="0.625rem"
+          height="0.75rem"
           viewBox="0 0 10 10"
           preserveAspectRatio="xMidYMid meet"
         >
           <circle
             cx="5"
             cy="5"
-            r="3.6"
+            r="3.8"
             fill="none"
             stroke="currentColor"
-            strokeWidth="1.2"
+            strokeWidth="1.1"
             opacity="0.28"
           />
           <path
-            d="M5 1.4 A 3.6 3.6 0 1 1 1.4 5"
+            d="M5 1.2 A 3.8 3.8 0 1 1 1.2 5"
             fill="none"
             stroke="currentColor"
-            strokeWidth="1.4"
+            strokeWidth="1.3"
             strokeLinecap="round"
           >
             <animateTransform
@@ -87,26 +91,31 @@ export function SidebarStatusIcon({
 
   if (status === "failed") {
     return (
-      <IconFrame colorClass="text-destructive" className={className}>
+      <IconFrame
+        colorClass={
+          emphasized ? "text-sidebar-primary" : "text-sidebar-primary/65"
+        }
+        className={className}
+      >
         <svg
-          width="0.625rem"
+          width="0.75rem"
-          height="0.625rem"
+          height="0.75rem"
           viewBox="0 0 10 10"
           preserveAspectRatio="xMidYMid meet"
         >
           <circle
             cx="5"
             cy="5"
-            r="3.8"
+            r="3.9"
             fill="none"
             stroke="currentColor"
-            strokeWidth="1.2"
+            strokeWidth="1.1"
           />
           <path
-            d="M3.5 3.5L6.5 6.5M6.5 3.5L3.5 6.5"
+            d="M3.4 3.4L6.6 6.6M6.6 3.4L3.4 6.6"
             fill="none"
             stroke="currentColor"
-            strokeWidth="1.4"
+            strokeWidth="1.3"
             strokeLinecap="round"
           />
         </svg>
@@ -116,20 +125,25 @@ export function SidebarStatusIcon({
 
   if (status === "active") {
     return (
-      <IconFrame colorClass="text-sidebar-primary" className={className}>
+      <IconFrame
+        colorClass={
+          emphasized ? "text-sidebar-primary" : "text-sidebar-primary/65"
+        }
+        className={className}
+      >
         <svg
-          width="0.625rem"
+          width="0.75rem"
-          height="0.625rem"
+          height="0.75rem"
           viewBox="0 0 10 10"
           preserveAspectRatio="xMidYMid meet"
         >
           <circle
             cx="5"
             cy="5"
-            r="3.8"
+            r="3.9"
             fill="none"
             stroke="currentColor"
-            strokeWidth="1.2"
+            strokeWidth="1.1"
             opacity="0.35"
           />
           <circle cx="5" cy="5" r="2" fill="currentColor" />
@@ -139,14 +153,34 @@ export function SidebarStatusIcon({
   }
 
   return (
-    <IconFrame colorClass="text-sidebar-primary/40" className={className}>
+    <IconFrame
+      colorClass={
+        emphasized ? "text-sidebar-primary/75" : "text-sidebar-primary/40"
+      }
+      className={className}
+    >
       <svg
-        width="0.625rem"
+        width="0.75rem"
-        height="0.625rem"
+        height="0.75rem"
         viewBox="0 0 10 10"
         preserveAspectRatio="xMidYMid meet"
       >
-        <circle cx="5" cy="5" r="3" fill="currentColor" />
+        <circle
+          cx="5"
+          cy="5"
+          r="3.9"
+          fill="none"
+          stroke="currentColor"
+          strokeWidth="1.1"
+        />
+        <path
+          d="M3.2 5.1 L4.4 6.3 L6.9 3.6"
+          fill="none"
+          stroke="currentColor"
+          strokeWidth="1.3"
+          strokeLinecap="round"
+          strokeLinejoin="round"
+        />
       </svg>
     </IconFrame>
   )