perf: route PTY stream through a single shared IPC listener

Every pane registered its own global onPtyData/onPtyExit listener, so each
output chunk woke N listeners and N-1 discarded it after an id compare.
With many terminals under heavy output that fan-out is pure overhead.
Now one IPC listener dispatches through a Map keyed by sessionId: one
lookup per chunk, only the owning pane runs.

src/renderer/src/terminal/TerminalView.tsx

@@ -9,11 +9,11 @@ import '@xterm/xterm/css/xterm.css'
 import { ClearOutlined, CopyOutlined, FolderOpenOutlined, PauseOutlined, SearchOutlined, SelectOutlined, SnippetsOutlined, SoundOutlined } from '@ant-design/icons'
 import { getThemeById } from '@shared/theme'
 import type { CommandItem } from '@shared/commands'
-import type { PtyDataEvent, PtyExitEvent } from '@shared/ipc'
 import type { TerminalSettings } from '@shared/settings'
 import { useSettingsStore } from '@renderer/settings/store'
 import { writeBroadcast } from '@renderer/workspace/broadcastStore'
 import { compileRules, HighlightStream, type CompiledRule } from './highlightEngine'
+import { subscribePtyData, subscribePtyExit } from './ptyDispatcher'
 import { cdArgument, conemuCwd } from './cwdTracker'
 import { getSessionCwd, setSessionCwd } from '@renderer/workspace/sessionCwdStore'
 import './terminal.css'
@@ -792,18 +792,19 @@ export const TerminalView: ForwardRefExoticComponent<TerminalViewProps & { ref?:
     let replayDone = false
     const pending: string[] = []
     const unsubscribes: (() => void)[] = [
-      window.api.onPtyData((e: PtyDataEvent) => {
-        if (e.id !== sessionId || deadRef.current) return
+      // Routed via the shared dispatcher (one IPC listener for all panes)
+      // instead of a per-pane global listener.
+      subscribePtyData(sessionId, (data: string) => {
+        if (deadRef.current) return
         if (!replayDone) {
-          pending.push(e.data)
+          pending.push(data)
           return
         }
-        writeHighlighted(e.data)
+        writeHighlighted(data)
       }),
-      window.api.onPtyExit((e: PtyExitEvent) => {
-        if (e.id !== sessionId) return
+      subscribePtyExit(sessionId, (code: number) => {
         deadRef.current = true
-        setExitCode(e.exitCode)
+        setExitCode(code)
         setDead(true)
       })
     ]

src/renderer/src/terminal/ptyDispatcher.ts

@@ -0,0 +1,48 @@
+import type { PtyDataEvent, PtyExitEvent } from '@shared/ipc'
+
+/**
+ * Single shared PTY stream listener. Every pane used to register its own
+ * window.api.onPtyData/onPtyExit listener, so each output chunk woke N
+ * listeners (N = pane count) and N-1 of them discarded it after an id
+ * compare. With many terminals under heavy output that per-chunk fan-out is
+ * pure overhead. Here one IPC listener dispatches through a Map keyed by
+ * sessionId: one lookup per chunk, and only the owning pane runs.
+ */
+
+type DataHandler = (data: string) => void
+type ExitHandler = (exitCode: number) => void
+
+const dataHandlers = new Map<string, DataHandler>()
+const exitHandlers = new Map<string, ExitHandler>()
+let bound = false
+
+function ensureBound(): void {
+  if (bound) return
+  bound = true
+  window.api.onPtyData((e: PtyDataEvent) => {
+    dataHandlers.get(e.id)?.(e.data)
+  })
+  window.api.onPtyExit((e: PtyExitEvent) => {
+    exitHandlers.get(e.id)?.(e.exitCode)
+  })
+}
+
+/** Subscribe to one session's output. Returns the unsubscribe function. */
+export function subscribePtyData(id: string, cb: DataHandler): () => void {
+  ensureBound()
+  dataHandlers.set(id, cb)
+  return () => {
+    // A rebind (template apply) may have replaced the handler already; only
+    // delete when this subscription is still the registered one.
+    if (dataHandlers.get(id) === cb) dataHandlers.delete(id)
+  }
+}
+
+/** Subscribe to one session's exit. Returns the unsubscribe function. */
+export function subscribePtyExit(id: string, cb: ExitHandler): () => void {
+  ensureBound()
+  exitHandlers.set(id, cb)
+  return () => {
+    if (exitHandlers.get(id) === cb) exitHandlers.delete(id)
+  }
+}