feat(mod_format): Add check-only formatting with interactive diff preview; make formatting default to dry-run and extend formatting API

ts/mod_config/index.ts

@@ -2,10 +2,32 @@
 
 import * as plugins from './mod.plugins.js';
 import { ReleaseConfig } from './classes.releaseconfig.js';
-import { runFormatter } from '../mod_format/index.js';
+import { runFormatter, type ICheckResult } from '../mod_format/index.js';
 
 export { ReleaseConfig };
 
+/**
+ * Format npmextra.json with diff preview
+ * Shows diff first, asks for confirmation, then applies
+ */
+async function formatNpmextraWithDiff(): Promise<void> {
+  // Check for diffs first
+  const checkResult = await runFormatter('npmextra', {
+    checkOnly: true,
+    showDiff: true,
+  }) as ICheckResult | void;
+
+  if (checkResult && checkResult.hasDiff) {
+    const shouldApply = await plugins.smartinteract.SmartInteract.getCliConfirmation(
+      'Apply formatting changes to npmextra.json?',
+      true
+    );
+    if (shouldApply) {
+      await runFormatter('npmextra', { silent: true });
+    }
+  }
+}
+
 export const run = async (argvArg: any) => {
   const command = argvArg._?.[1];
   const value = argvArg._?.[2];
@@ -149,8 +171,8 @@ async function handleAdd(url?: string): Promise<void> {
 
   if (added) {
     await config.save();
-    await runFormatter('npmextra', { silent: true });
     plugins.logger.log('success', `Added registry: ${url}`);
+    await formatNpmextraWithDiff();
   } else {
     plugins.logger.log('warn', `Registry already exists: ${url}`);
   }
@@ -185,8 +207,8 @@ async function handleRemove(url?: string): Promise<void> {
 
   if (removed) {
     await config.save();
-    await runFormatter('npmextra', { silent: true });
     plugins.logger.log('success', `Removed registry: ${url}`);
+    await formatNpmextraWithDiff();
   } else {
     plugins.logger.log('warn', `Registry not found: ${url}`);
   }
@@ -212,8 +234,8 @@ async function handleClear(): Promise<void> {
   if (confirmed) {
     config.clearRegistries();
     await config.save();
-    await runFormatter('npmextra', { silent: true });
     plugins.logger.log('success', 'All registries cleared.');
+    await formatNpmextraWithDiff();
   } else {
     plugins.logger.log('info', 'Operation cancelled.');
   }
@@ -252,8 +274,8 @@ async function handleAccessLevel(level?: string): Promise<void> {
 
   config.setAccessLevel(level as 'public' | 'private');
   await config.save();
-  await runFormatter('npmextra', { silent: true });
   plugins.logger.log('success', `Access level set to: ${level}`);
+  await formatNpmextraWithDiff();
 }
 
 /**