refactor: simplify middleware, controller and service init

internal/service/oauth_broker_service.go

@@ -1,6 +1,8 @@
 package service
 
 import (
+	"context"
+
 	"github.com/tinyauthapp/tinyauth/internal/model"
 	"github.com/tinyauthapp/tinyauth/internal/utils/logger"
 
@@ -25,7 +27,7 @@ type OAuthBrokerService struct {
 	configs  map[string]model.OAuthServiceConfig
 }
 
-var presets = map[string]func(config model.OAuthServiceConfig) *OAuthService{
+var presets = map[string]func(config model.OAuthServiceConfig, ctx context.Context) *OAuthService{
 	"github": newGitHubOAuthService,
 	"google": newGoogleOAuthService,
 }
@@ -33,25 +35,25 @@ var presets = map[string]func(config model.OAuthServiceConfig) *OAuthService{
 func NewOAuthBrokerService(
 	log *logger.Logger,
 	configs map[string]model.OAuthServiceConfig,
+	ctx context.Context,
 ) *OAuthBrokerService {
-	return &OAuthBrokerService{
+	service := &OAuthBrokerService{
 		log:      log,
 		services: make(map[string]OAuthServiceImpl),
 		configs:  configs,
 	}
-}
 
-func (broker *OAuthBrokerService) Init() error {
-	for name, cfg := range broker.configs {
+	for name, cfg := range configs {
 		if presetFunc, exists := presets[name]; exists {
-			broker.services[name] = presetFunc(cfg)
-			broker.log.App.Debug().Str("service", name).Msg("Loaded OAuth service from preset")
+			service.services[name] = presetFunc(cfg, ctx)
+			service.log.App.Debug().Str("service", name).Msg("Loaded OAuth service from preset")
 		} else {
-			broker.services[name] = NewOAuthService(cfg, name)
-			broker.log.App.Debug().Str("service", name).Msg("Loaded OAuth service from custom config")
+			service.services[name] = NewOAuthService(cfg, name, ctx)
+			service.log.App.Debug().Str("service", name).Msg("Loaded OAuth service from custom config")
 		}
 	}
-	return nil
+
+	return service
 }
 
 func (broker *OAuthBrokerService) GetConfiguredServices() []string {