feat: 更新配置文档

backend/internal/config/config.go

@@ -5,6 +5,7 @@ import (
 	"os"
 	"strings"
 
+	"github.com/joho/godotenv"
 	"github.com/spf13/viper"
 )
 
@@ -50,6 +51,7 @@ type AIConfig struct {
 type STTConfig struct {
 	Provider string `mapstructure:"provider"`
 	APIKey   string `mapstructure:"api_key"`
+	Model    string `mapstructure:"model"`
 	Endpoint string `mapstructure:"endpoint"`
 }
 
@@ -64,6 +66,7 @@ type LLMConfig struct {
 type TTSConfig struct {
 	Provider string  `mapstructure:"provider"`
 	APIKey   string  `mapstructure:"api_key"`
+	Model    string  `mapstructure:"model"`
 	Voice    string  `mapstructure:"voice"`
 	Speed    float64 `mapstructure:"speed"`
 	Endpoint string  `mapstructure:"endpoint"`
@@ -98,12 +101,14 @@ func Load() (*Config, error) {
 	v.SetDefault("redis.addr", "localhost:6379")
 	v.SetDefault("redis.db", 0)
 	v.SetDefault("ai.stt.provider", "deepgram")
+	v.SetDefault("ai.stt.model", "nova-2")
 	v.SetDefault("ai.stt.endpoint", "wss://api.deepgram.com/v1/listen")
 	v.SetDefault("ai.llm.provider", "openai")
 	v.SetDefault("ai.llm.model", "gpt-4o")
 	v.SetDefault("ai.llm.endpoint", "https://api.openai.com/v1")
 	v.SetDefault("ai.llm.timeout", 10)
 	v.SetDefault("ai.tts.provider", "openai")
+	v.SetDefault("ai.tts.model", "tts-1")
 	v.SetDefault("ai.tts.voice", "alloy")
 	v.SetDefault("ai.tts.speed", 1.0)
 	v.SetDefault("ai.tts.endpoint", "https://api.openai.com/v1")
@@ -125,6 +130,11 @@ func Load() (*Config, error) {
 		_ = v.MergeInConfig()
 	}
 
+	// 加载 .env 文件（不覆盖已有环境变量）
+	// 按优先级尝试：当前目录、上级目录（兼容从 backend/ 或项目根目录启动）
+	_ = godotenv.Load()
+	_ = godotenv.Load("../.env")
+
 	// 环境变量覆盖
 	v.SetEnvPrefix("CAMTALK")
 	v.SetEnvKeyReplacer(strings.NewReplacer(".", "_"))