feat(format): add check and fix workflows

ts/mod_format/classes.baseformatter.ts

@@ -1,6 +1,10 @@
 import * as plugins from './mod.plugins.js';
 import { FormatContext } from './classes.formatcontext.js';
-import type { IPlannedChange, ICheckResult } from './interfaces.format.js';
+import type {
+  IPlannedChange,
+  ICheckResult,
+  IFormatWarning,
+} from './interfaces.format.js';
 import { Project } from '../classes.project.js';
 import { FormatStats } from './classes.formatstats.js';
 
@@ -19,6 +23,14 @@ export abstract class BaseFormatter {
   abstract analyze(): Promise<IPlannedChange[]>;
   abstract applyChange(change: IPlannedChange): Promise<void>;
 
+  get runsWithoutChanges(): boolean {
+    return false;
+  }
+
+  async validate(): Promise<IFormatWarning[]> {
+    return [];
+  }
+
   async execute(changes: IPlannedChange[]): Promise<void> {
     const startTime = this.stats.moduleStartTime(this.name);
     this.stats.startModule(this.name);