fix(server): /api/stacks does not handles primaryAssetId query param (#16868)

fix(server): add missing validation decorator

open-api/immich-openapi-specs.json

@@ -5712,6 +5712,7 @@
             "required": false,
             "in": "query",
             "schema": {
+              "format": "uuid",
               "type": "string"
             }
           }

server/src/dtos/stack.dto.ts

@@ -12,6 +12,7 @@ export class StackCreateDto {
 }
 
 export class StackSearchDto {
+  @ValidateUUID({ optional: true })
   primaryAssetId?: string;
 }