Fix sidebar highlighting for draft threads (pingdotgg#4679)

(cherry picked from commit 6a3df51)

Author: juliusmarminge

apps/web/src/components/SidebarV2.tsx

@@ -96,7 +96,11 @@ import { threadEnvironment } from "../state/threads";
 import { projectEnvironment } from "../state/projects";
 import { useEnvironmentQuery } from "../state/query";
 import { useAtomCommand } from "../state/use-atom-command";
-import { buildThreadRouteParams, resolveThreadRouteTarget } from "../threadRoutes";
+import {
+  buildThreadRouteParams,
+  resolveActiveThreadRouteRef,
+  resolveThreadRouteTarget,
+} from "../threadRoutes";
 import { formatRelativeTimeLabel, parseTimestampDate } from "../timestampFormat";
 import type { SidebarThreadSummary } from "../types";
 import { cn } from "~/lib/utils";
@@ -1052,7 +1056,13 @@ export default function SidebarV2() {
     strict: false,
     select: (params) => resolveThreadRouteTarget(params),
   });
-  const routeThreadRef = routeTarget?.kind === "server" ? routeTarget.threadRef : null;
+  const routeDraftThread = useComposerDraftStore((store) =>
+    routeTarget?.kind === "draft" ? store.getDraftSession(routeTarget.draftId) : null,
+  );
+  const routeThreadRef = useMemo(
+    () => resolveActiveThreadRouteRef(routeTarget, routeDraftThread),
+    [routeDraftThread, routeTarget],
+  );
   const routeThreadKey = routeThreadRef ? scopedThreadKey(routeThreadRef) : null;
   const routeTargetRef = useRef(routeTarget);
   routeTargetRef.current = routeTarget;