fix(lint): fix 4 golangci-lint failures on main branch

- idp_service.go: correct Scopes field alignment to col 13 (was 5 spaces,
  needs 6 to match AuthUrl/TokenUrl/UserInfoUrl group); revert over-correction
  from previous commit that wrongly added FieldMapping to the alignment group
- instance_service.go: add default case to switch on updateSetting.Key to
  satisfy revive switch-without-default rule
- memo_service.go: fix unchecked type assertion in isSSESuppressed; use
  ok && v pattern instead of discarding the ok bool
- sse_service_test.go: remove unused drainEvents helper function

https://claude.ai/code/session_01DVhwUL8RG8HVrcChv5qHdh

server/router/api/v1/idp_service.go

@@ -182,10 +182,10 @@ func convertIdentityProviderFromStore(identityProvider *storepb.IdentityProvider
 				Oauth2Config: &v1pb.OAuth2Config{
 					ClientId: oauth2Config.ClientId,
 					// ClientSecret is write-only: never returned in responses.
-					AuthUrl:      oauth2Config.AuthUrl,
-					TokenUrl:     oauth2Config.TokenUrl,
-					UserInfoUrl:  oauth2Config.UserInfoUrl,
-					Scopes:       oauth2Config.Scopes,
+					AuthUrl:     oauth2Config.AuthUrl,
+					TokenUrl:    oauth2Config.TokenUrl,
+					UserInfoUrl: oauth2Config.UserInfoUrl,
+					Scopes:      oauth2Config.Scopes,
 					FieldMapping: &v1pb.FieldMapping{
 						Identifier:  oauth2Config.FieldMapping.Identifier,
 						DisplayName: oauth2Config.FieldMapping.DisplayName,

server/router/api/v1/instance_service.go

@@ -127,6 +127,8 @@ func (s *APIV1Service) UpdateInstanceSetting(ctx context.Context, request *v1pb.
 				storage.S3Config.AccessKeySecret = existing.S3Config.AccessKeySecret
 			}
 		}
+	default:
+		// No credential preservation needed for other setting types.
 	}
 
 	instanceSetting, err := s.Store.UpsertInstanceSetting(ctx, updateSetting)

server/router/api/v1/memo_service.go

@@ -28,8 +28,8 @@ func withSuppressSSE(ctx context.Context) context.Context {
 }
 
 func isSSESuppressed(ctx context.Context) bool {
-	v, _ := ctx.Value(suppressSSEKey{}).(bool)
-	return v
+	v, ok := ctx.Value(suppressSSEKey{}).(bool)
+	return ok && v
 }
 
 func (s *APIV1Service) CreateMemo(ctx context.Context, request *v1pb.CreateMemoRequest) (*v1pb.Memo, error) {

server/router/api/v1/sse_service_test.go

@@ -32,20 +32,6 @@ func userCtx(ctx context.Context, userID int32) context.Context {
 	return context.WithValue(ctx, auth.UserIDContextKey, userID)
 }
 
-// drainEvents reads all events currently buffered in the channel and returns
-// them as a string slice.  It stops as soon as the channel is empty (non-blocking).
-func drainEvents(ch <-chan []byte) []string {
-	var out []string
-	for {
-		select {
-		case data := <-ch:
-			out = append(out, string(data))
-		default:
-			return out
-		}
-	}
-}
-
 // collectEventsFor reads events from ch for the given duration and returns them.
 func collectEventsFor(ch <-chan []byte, d time.Duration) []string {
 	var out []string