tui: add keyboard shortcuts to cycle through recently used models

Users can now press F2 to cycle forward and Shift+F2 to cycle backward through their recently used models, making it faster to switch between commonly used AI models without opening the model selection dialog.

packages/opencode/src/cli/cmd/tui/app.tsx

@@ -172,6 +172,24 @@ function App() {
         dialog.replace(() => <DialogModel />)
       },
     },
+    {
+      title: "Model cycle",
+      value: "model.cycle_recent",
+      keybind: "model_cycle_recent",
+      category: "Agent",
+      onSelect: () => {
+        local.model.cycle(1)
+      },
+    },
+    {
+      title: "Model cycle reverse",
+      value: "model.cycle_recent_reverse",
+      keybind: "model_cycle_recent_reverse",
+      category: "Agent",
+      onSelect: () => {
+        local.model.cycle(-1)
+      },
+    },
     {
       title: "Switch agent",
       value: "agent.list",