adjust collection; adjust migration

internal/apikeys/service.go

@@ -193,7 +193,7 @@ func randomToken(size int) (string, error) {
 
 func canonicalPermissions(perms []string) []string {
 	if len(perms) == 0 {
-		return nil
+		return []string{}
 	}
 
 	seen := make(map[string]struct{}, len(perms))
@@ -214,7 +214,7 @@ func canonicalPermissions(perms []string) []string {
 
 func uniqueUint(values []uint) []uint {
 	if len(values) == 0 {
-		return nil
+		return []uint{}
 	}
 
 	seen := make(map[uint]struct{}, len(values))