feat: Implement Steam login initialization logic

- Added SteamLoginInitLogic to handle the initiation of Steam login.
- Created service context for managing configuration and Redis connection.
- Defined types for Steam login requests and callbacks.
- Implemented utility functions for building OpenID query strings and validating responses from Steam.
- Updated go.mod and go.sum to include necessary dependencies.
- Modified GenApi.ps1 script to generate code in the correct directory.

app/internal/svc/servicecontext.go

@@ -0,0 +1,19 @@
+package svc
+
+import (
+	"git.cialloo.com/CiallooWeb/Authenticator/app/internal/config"
+
+	"github.com/zeromicro/go-zero/core/stores/redis"
+)
+
+type ServiceContext struct {
+	Config config.Config
+	Redis  *redis.Redis
+}
+
+func NewServiceContext(c config.Config) *ServiceContext {
+	return &ServiceContext{
+		Config: c,
+		Redis:  redis.MustNewRedis(c.Redis),
+	}
+}