feat: add Codex CLI detection and model management APIs

- Implemented IPC handlers for checking Codex CLI installation status, retrieving available models, and checking provider statuses.
- Enhanced the SettingsView to include OpenAI API key management and connection testing.
- Updated the feature executor to support multiple model providers (Claude and Codex), allowing for improved flexibility in feature execution.
- Introduced utility functions to determine model types and support for thinking controls.

This update enhances the application's capabilities by integrating Codex CLI support and improving model management, providing users with a more robust experience.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

app/src/lib/utils.ts

@@ -1,6 +1,55 @@
 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",
+    "o3",
+    "o3-mini",
+    "o4-mini",
+    "gpt-4o",
+    "gpt-4o-mini",
+  ];
+  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",
+    o3: "OpenAI O3",
+    "o3-mini": "OpenAI O3 Mini",
+    "o4-mini": "OpenAI O4 Mini",
+    "gpt-4o": "GPT-4o",
+    "gpt-4o-mini": "GPT-4o Mini",
+  };
+  return displayNames[model] || model;
+}