fix(clients): open a delegated child's approval on the environment it runs in

apps/mobile/src/features/threads/ThreadDetailScreen.tsx

@@ -731,7 +731,7 @@ function ThreadDetailBody(props: ThreadDetailScreenProps) {
         accessibilityLabel: `Open ${childInput.hasPendingApprovals ? "approval" : "question"} from ${childInput.title}`,
         onPress: () => {
           Keyboard.dismiss();
-          openLinkedThread({ environmentId: props.environmentId, threadId: childInput.id });
+          openLinkedThread({ environmentId: childInput.environmentId, threadId: childInput.id });
         },
       };
     }

apps/web/src/components/chat/ThreadActivityBanners.tsx

@@ -1,4 +1,5 @@
 import type {
+  EnvironmentId,
   OrchestrationV2PendingBackgroundTask,
   OrchestrationV2ProviderGoal,
   ThreadId,
@@ -34,7 +35,8 @@ import type { ThreadNowItem } from "./ThreadNow";
 export function childInputNowItem(input: {
   readonly childThreadInputs: ReadonlyArray<EnvironmentThreadShell>;
   readonly parentAwaitingUser: boolean;
-  readonly onOpenThread: (threadId: ThreadId) => void;
+  // A task delegated to a linked environment lives there, not where the parent runs.
+  readonly onOpenThread: (threadId: ThreadId, environmentId: EnvironmentId) => void;
 }): (ThreadNowItem & { readonly waitingLabel: string }) | null {
   const { childThreadInputs, onOpenThread } = input;
   const first = childThreadInputs[0];
@@ -55,15 +57,15 @@ export function childInputNowItem(input: {
       <Fragment key={child.id}>
         {index > 0 ? " " : null}
         <span className="whitespace-nowrap">
-          <InlineButton tone="muted" onClick={() => onOpenThread(child.id)}>
+          <InlineButton tone="muted" onClick={() => onOpenThread(child.id, child.environmentId)}>
             {child.title}
           </InlineButton>
           {index < childThreadInputs.length - 1 ? "," : null}
         </span>
       </Fragment>
     )),
     actions: (
-      <InlineButton onClick={() => onOpenThread(first.id)}>
+      <InlineButton onClick={() => onOpenThread(first.id, first.environmentId)}>
         {first.hasPendingApprovals ? "Open approval" : "Open question"}
       </InlineButton>
     ),

apps/web/src/components/chat/useThreadLifecycle.tsx

@@ -51,6 +51,7 @@ import { useEnvironmentScope } from "~/state/session";
 import { threadEnvironment } from "../../state/threads";
 import { vcsEnvironment } from "../../state/vcs";
 import { useChildThreadInputs, readThreadShell, waitForThreadShell } from "../../state/entities";
+import { serverEnvironment } from "../../state/server";
 import { environmentShell } from "../../state/shell";
 import { ThreadStatusLine } from "./ThreadStatusLine";
 import { formatRelativeTimeLabel } from "../../timestampFormat";
@@ -427,14 +428,20 @@ export function useThreadLifecycle(input: ThreadLifecycleInput) {
   };
   const handleStopBackgroundWorkStable = useStableCallback(handleStopBackgroundWork);
   const openRelatedThreadGenerationRef = useRef(0);
-  const onOpenRelatedThread = async (threadId: ThreadId) => {
+  // A task delegated to a linked environment opens there; the default is this thread's own.
+  const onOpenRelatedThread = async (
+    threadId: ThreadId,
+    threadEnvironmentId: EnvironmentId = environmentId,
+  ) => {
     const generation = ++openRelatedThreadGenerationRef.current;
-    const threadRef = scopeThreadRef(environmentId, threadId);
+    const threadRef = scopeThreadRef(threadEnvironmentId, threadId);
     const isEnvironmentLive = () =>
-      appAtomRegistry.get(environmentShell.stateValueAtom(environmentId)).status === "live";
+      appAtomRegistry.get(environmentShell.stateValueAtom(threadEnvironmentId)).status === "live";
     // The shell can leave idle subagent children out, so absence is not deletion there: the
     // route decides from the thread's own detail.
-    const shellOmitsChildren = serverConfig?.shellThreadFamilies === true;
+    const shellOmitsChildren =
+      appAtomRegistry.get(serverEnvironment.configValueAtom(threadEnvironmentId))
+        ?.shellThreadFamilies === true;
     // A just-launched child can reach this timeline before its shell syncs.
     if (!shellOmitsChildren && isEnvironmentLive() && readThreadShell(threadRef) === null) {
       const location = router.latestLocation;