Put the cursor in the terminal after sending a note

Sending already switched to the target terminal's tab, which looks like it
should be enough: `TerminalView` focuses xterm whenever a terminal becomes
active. But that effect keys off `active`, so it only fires on a *change* —
and the dock's ordinary case is sending to the terminal already on screen.
`setActiveTabKey` writes the key that is already set, nothing changes, no
effect re-runs, and focus stays on the Send button. The note is sitting in the
prompt and the user still has to click the terminal before pressing Enter.

So the send now asks for focus explicitly, through a one-shot request in the
store that `TerminalView` consumes and clears — the shape `pendingHomeTab`
already uses. Clearing is not tidiness: hold the id and the second send to the
same terminal writes a value that is already there, which is precisely the
no-op this exists to fix.

Focus is requested only on success. A failed send toasts and leaves the user
where they are, because there is nothing in the prompt to press Enter on.

The three `TerminalView` tests give focus away after mounting before making
any assertion, so what they observe is the request landing and never the focus
that `active` already grants on mount — which would pass with the feature
absent.

752 tests pass, 62 files.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_011YPqHpjV4EL6RNEwrRKqQm

app/src/components/terminal/TerminalView.tsx

@@ -731,6 +731,21 @@ export default function TerminalView({ sessionId, active }: Props) {
     }
   }, [active, gpuRenderingSetting]);
 
+  // Focus on demand, for the caller that cannot rely on the effect above.
+  // That one keys off `active`, so it covers switching *to* a terminal and
+  // nothing else — and the notes dock sends to the terminal already on screen,
+  // where `active` never changes. Consumed once and cleared, so asking twice
+  // for the same terminal works.
+  const pendingTerminalFocus = useAppState((s) => s.pendingTerminalFocus);
+  const clearPendingTerminalFocus = useAppState(
+    (s) => s.clearPendingTerminalFocus,
+  );
+  useEffect(() => {
+    if (pendingTerminalFocus !== sessionId) return;
+    termRef.current?.focus();
+    clearPendingTerminalFocus();
+  }, [pendingTerminalFocus, sessionId, clearPendingTerminalFocus]);
+
   // Auto-dismiss toast after 30 seconds — unless the user is standing in it.
   // A keyboard user who has just jumped into the toast is mid-decision, and
   // pulling it out from under them costs them the only route to finishing a