🤖 Fix Cmd+Shift+T keybind failing in new chats

The toggle thinking keybind (Cmd+Shift+T) would fail in new chats because it
checked message history for the current model, which is null until the first
message is sent. However, users can see and select a model in the UI
immediately (stored in localStorage).

Root cause: State source mismatch
- UI shows: selectedModel from localStorage (always available)
- Keybind checked: currentModel from message history (null in new chats)

Fix: Read the selected model from localStorage and fall back to message
history model if not set. This matches what the user sees in the UI.

Now the keybind works immediately in new chats, matching user expectations.

_Generated with `cmux`_

Author: ammar-agent

src/hooks/useAIViewKeybinds.ts

@@ -1,7 +1,7 @@
 import { useEffect } from "react";
 import type { ChatInputAPI } from "@/components/ChatInput";
 import { matchesKeybind, KEYBINDS, isEditableElement } from "@/utils/ui/keybinds";
-import { getLastThinkingByModelKey } from "@/constants/storage";
+import { getLastThinkingByModelKey, getModelKey } from "@/constants/storage";
 import { updatePersistedState, readPersistedState } from "@/hooks/usePersistedState";
 import type { ThinkingLevel, ThinkingLevelOn } from "@/types/thinking";
 import { DEFAULT_THINKING_LEVEL } from "@/types/thinking";
@@ -64,17 +64,22 @@ export function useAIViewKeybinds({
       if (matchesKeybind(e, KEYBINDS.TOGGLE_THINKING)) {
         e.preventDefault();
 
-        // Skip if no model set (workspace has no messages yet)
-        if (!currentModel) {
+        // Get selected model from localStorage (what user sees in UI)
+        // Fall back to message history model if not set
+        const selectedModel = readPersistedState<string | null>(getModelKey(workspaceId), null);
+        const modelToUse = selectedModel ?? currentModel;
+
+        // Skip if no model set at all
+        if (!modelToUse) {
           return;
         }
 
         // Storage key for remembering this model's last-used active thinking level
-        const lastThinkingKey = getLastThinkingByModelKey(currentModel);
+        const lastThinkingKey = getLastThinkingByModelKey(modelToUse);
 
         // Special-case: if model has single-option policy (e.g., gpt-5-pro only supports HIGH),
         // the toggle is a no-op to avoid confusing state transitions.
-        const allowed = getThinkingPolicyForModel(currentModel);
+        const allowed = getThinkingPolicyForModel(modelToUse);
         if (allowed.length === 1) {
           return; // No toggle for single-option policies
         }