feat: 添加环境变量写入功能

- Claude Code: 写入 ANTHROPIC_BASE_URL, ANTHROPIC_AUTH_TOKEN
- Codex: 写入 OPENAI_API_KEY, OPENAI_BASE_URL
- Bash 脚本: 自动检测 shell 配置文件 (.bashrc/.zshrc/.profile)
- PowerShell 脚本: 使用 [Environment]::SetEnvironmentVariable 设置用户环境变量
- 添加 API key 格式验证
- 修复文件末尾换行问题，使用单引号包裹值更安全

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

Co-Authored-By: Claude <noreply@anthropic.com>

codex/setup-codex.ps1

@@ -18,6 +18,19 @@ $DefaultBaseUrl = "https://api2.xcodecli.com"
 $CodexConfigDir = "$env:USERPROFILE\.codex"
 $CodexConfigFile = "$CodexConfigDir\config.toml"
 
+# Function to write environment variable (User level)
+function Set-EnvVariable {
+    param(
+        [string]$Name,
+        [string]$Value
+    )
+    # Set for current session
+    [Environment]::SetEnvironmentVariable($Name, $Value, [System.EnvironmentVariableTarget]::Process)
+    # Set permanently for user
+    [Environment]::SetEnvironmentVariable($Name, $Value, [System.EnvironmentVariableTarget]::User)
+    Write-Info "Environment variable set: $Name"
+}
+
 # Color functions for output
 function Write-Info {
     param([string]$Message)
@@ -192,6 +205,13 @@ env_key = "OPENAI_API_KEY"
         $authJsonPath = "$CodexConfigDir\auth.json"
         $authJson | ConvertTo-Json | Set-Content -Path $authJsonPath -Encoding UTF8
         Write-Success "Codex auth file written to: $authJsonPath"
+
+        # Set environment variables
+        Write-Info "Setting environment variables..."
+        Set-EnvVariable -Name "OPENAI_API_KEY" -Value $ApiKey
+        Set-EnvVariable -Name "OPENAI_BASE_URL" -Value "$BaseUrl/v1"
+        Write-Success "Environment variables configured"
+
         return $true
     }
     catch {