feat(ui): active agents panel, sidebar context, and page enhancements

Add live ActiveAgentsPanel with real-time transcript feed, SidebarContext
for responsive sidebar state, agent config form with reasoning effort,
improved inbox with failed run alerts, enriched issue detail with project
picker, and various component refinements across pages.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

ui/src/components/NewIssueDialog.tsx

@@ -95,6 +95,7 @@ export function NewIssueDialog() {
   const [statusOpen, setStatusOpen] = useState(false);
   const [priorityOpen, setPriorityOpen] = useState(false);
   const [assigneeOpen, setAssigneeOpen] = useState(false);
+  const [assigneeSearch, setAssigneeSearch] = useState("");
   const [projectOpen, setProjectOpen] = useState(false);
   const [moreOpen, setMoreOpen] = useState(false);
 
@@ -341,14 +342,21 @@ export function NewIssueDialog() {
           </Popover>
 
           {/* Assignee chip */}
-          <Popover open={assigneeOpen} onOpenChange={setAssigneeOpen}>
+          <Popover open={assigneeOpen} onOpenChange={(open) => { setAssigneeOpen(open); if (!open) setAssigneeSearch(""); }}>
             <PopoverTrigger asChild>
               <button className="inline-flex items-center gap-1.5 rounded-md border border-border px-2 py-1 text-xs hover:bg-accent/50 transition-colors">
                 <User className="h-3 w-3 text-muted-foreground" />
                 {currentAssignee ? currentAssignee.name : "Assignee"}
               </button>
             </PopoverTrigger>
-            <PopoverContent className="w-44 p-1" align="start">
+            <PopoverContent className="w-52 p-1" align="start">
+              <input
+                className="w-full px-2 py-1.5 text-xs bg-transparent outline-none border-b border-border mb-1 placeholder:text-muted-foreground/50"
+                placeholder="Search agents..."
+                value={assigneeSearch}
+                onChange={(e) => setAssigneeSearch(e.target.value)}
+                autoFocus
+              />
               <button
                 className={cn(
                   "flex items-center gap-2 w-full px-2 py-1.5 text-xs rounded hover:bg-accent/50",
@@ -358,7 +366,14 @@ export function NewIssueDialog() {
               >
                 No assignee
               </button>
-              {(agents ?? []).map((a) => (
+              {(agents ?? [])
+                .filter((a) => a.status !== "terminated")
+                .filter((a) => {
+                  if (!assigneeSearch.trim()) return true;
+                  const q = assigneeSearch.toLowerCase();
+                  return a.name.toLowerCase().includes(q);
+                })
+                .map((a) => (
                 <button
                   key={a.id}
                   className={cn(