Add oauth callback via proxy

Improved support for environment variables and configuration files, and standardized default behaviors

config/config.go

@@ -30,6 +30,7 @@ type Config struct {
 	Oss      Oss
 	Jwt      Jwt
 	Rustdesk Rustdesk
+	Proxy    Proxy
 }
 
 // Init 初始化配置

config/proxy.go

@@ -0,0 +1,6 @@
+package config
+
+type Proxy struct {
+	Enable bool   `mapstructure:"enable"`
+	Host   string `mapstructure:"host"`
+}