feat(app): better subagent experience (#20708)

packages/app/src/pages/session.tsx

@@ -429,6 +429,7 @@ export default function Page() {
   }
 
   const info = createMemo(() => (params.id ? sync.session.get(params.id) : undefined))
+  const isChildSession = createMemo(() => !!info()?.parentID)
   const diffs = createMemo(() => (params.id ? (sync.data.session_diff[params.id] ?? []) : []))
   const sessionCount = createMemo(() => Math.max(info()?.summary?.files ?? 0, diffs().length))
   const hasSessionReview = createMemo(() => sessionCount() > 0)
@@ -1058,7 +1059,7 @@ export default function Page() {
     }
 
     if (event.key.length === 1 && event.key !== "Unidentified" && !(event.ctrlKey || event.metaKey)) {
-      if (composer.blocked()) return
+      if (composer.blocked() || isChildSession()) return
       inputRef?.focus()
     }
   }
@@ -1127,7 +1128,10 @@ export default function Page() {
     setFileTreeTab("all")
   }
 
-  const focusInput = () => inputRef?.focus()
+  const focusInput = () => {
+    if (isChildSession()) return
+    inputRef?.focus()
+  }
 
   useSessionCommands({
     navigateMessageByOffset,
@@ -1658,7 +1662,7 @@ export default function Page() {
   const queueEnabled = createMemo(() => {
     const id = params.id
     if (!id) return false
-    return settings.general.followup() === "queue" && busy(id) && !composer.blocked()
+    return settings.general.followup() === "queue" && busy(id) && !composer.blocked() && !isChildSession()
   })
 
   const followupText = (item: FollowupDraft) => {
@@ -1690,6 +1694,7 @@ export default function Page() {
   const followupDock = createMemo(() => queuedFollowups().map((item) => ({ id: item.id, text: followupText(item) })))
 
   const sendFollowup = (sessionID: string, id: string, opts?: { manual?: boolean }) => {
+    if (sync.session.get(sessionID)?.parentID) return Promise.resolve()
     const item = (followup.items[sessionID] ?? []).find((entry) => entry.id === id)
     if (!item) return Promise.resolve()
     if (followupBusy(sessionID)) return Promise.resolve()
@@ -1820,6 +1825,7 @@ export default function Page() {
     if (followupBusy(sessionID)) return
     if (followup.failed[sessionID] === item.id) return
     if (followup.paused[sessionID]) return
+    if (isChildSession()) return
     if (composer.blocked()) return
     if (busy(sessionID)) return
 
@@ -2001,7 +2007,7 @@ export default function Page() {
             }}
             onResponseSubmit={resumeScroll}
             followup={
-              params.id
+              params.id && !isChildSession()
                 ? {
                     queue: queueEnabled,
                     items: followupDock(),