refactor: restructure project to monorepo with apps directory

apps/app/src/lib/utils.ts

@@ -0,0 +1,45 @@
+import { clsx, type ClassValue } from "clsx"
+import { twMerge } from "tailwind-merge"
+import type { AgentModel } from "@/store/app-store"
+
+export function cn(...inputs: ClassValue[]) {
+  return twMerge(clsx(inputs))
+}
+
+/**
+ * Check if a model is a Codex/OpenAI model (doesn't support thinking)
+ */
+export function isCodexModel(model?: AgentModel | string): boolean {
+  if (!model) return false;
+  const codexModels: string[] = [
+    "gpt-5.1-codex-max",
+    "gpt-5.1-codex",
+    "gpt-5.1-codex-mini",
+    "gpt-5.1",
+  ];
+  return codexModels.includes(model);
+}
+
+/**
+ * Determine if the current model supports extended thinking controls
+ */
+export function modelSupportsThinking(model?: AgentModel | string): boolean {
+  if (!model) return true;
+  return !isCodexModel(model);
+}
+
+/**
+ * Get display name for a model
+ */
+export function getModelDisplayName(model: AgentModel | string): string {
+  const displayNames: Record<string, string> = {
+    haiku: "Claude Haiku",
+    sonnet: "Claude Sonnet",
+    opus: "Claude Opus",
+    "gpt-5.1-codex-max": "GPT-5.1 Codex Max",
+    "gpt-5.1-codex": "GPT-5.1 Codex",
+    "gpt-5.1-codex-mini": "GPT-5.1 Codex Mini",
+    "gpt-5.1": "GPT-5.1",
+  };
+  return displayNames[model] || model;
+}