fix: promote CLAUDE.md to main template when group becomes main

When a non-main group is re-registered with --is-main, the existing
CLAUDE.md (copied from global template) lacked admin context. Now
register.ts detects this promotion case and replaces it with the main
template. Files that already contain "## Admin Context" are preserved.

Adds tests for:
- promoting non-main to main upgrades the template
- cross-channel promotion (e.g. Telegram non-main → main)
- promotion with custom assistant name
- re-registration preserves user-modified main CLAUDE.md
- re-registration preserves user-modified non-main CLAUDE.md

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

setup/register.test.ts

@@ -272,18 +272,24 @@ describe('CLAUDE.md template copy', () => {
     const folderDir = path.join(groupsDir, folder);
     fs.mkdirSync(path.join(folderDir, 'logs'), { recursive: true });
 
-    // Template copy (register.ts lines 119-138)
+    // Template copy + promotion (register.ts lines 119-148)
     const dest = path.join(folderDir, 'CLAUDE.md');
-    if (!fs.existsSync(dest)) {
     const templatePath = isMain
       ? path.join(groupsDir, 'main', 'CLAUDE.md')
       : path.join(groupsDir, 'global', 'CLAUDE.md');
+    const fileExists = fs.existsSync(dest);
+    const needsPromotion =
+      isMain &&
+      fileExists &&
+      !fs.readFileSync(dest, 'utf-8').includes('## Admin Context');
+
+    if (!fileExists || needsPromotion) {
       if (fs.existsSync(templatePath)) {
         fs.copyFileSync(templatePath, dest);
       }
     }
 
-    // Name update across all groups (register.ts lines 140-165)
+    // Name update across all groups (register.ts lines 150-175)
     if (assistantName !== 'Andy') {
       const mdFiles = fs
         .readdirSync(groupsDir)
@@ -401,19 +407,66 @@ describe('CLAUDE.md template copy', () => {
     }
   });
 
-  it('does not overwrite user-modified CLAUDE.md', () => {
+  it('does not overwrite main CLAUDE.md that already has admin context', () => {
     simulateRegister('slack_main', true);
-    // User customizes the file
-    fs.writeFileSync(
-      path.join(groupsDir, 'slack_main', 'CLAUDE.md'),
-      '# Custom\n\nUser-modified content.',
-    );
+    // User appends custom content to the main template
+    const mdPath = path.join(groupsDir, 'slack_main', 'CLAUDE.md');
+    fs.appendFileSync(mdPath, '\n\n## My Custom Section\n\nUser notes here.');
     // Re-registering same folder (e.g. re-running /add-slack)
     simulateRegister('slack_main', true);
 
     const content = readGroupMd('slack_main');
+    // Preserved: has both admin context AND user additions
+    expect(content).toContain('Admin Context');
+    expect(content).toContain('My Custom Section');
+  });
+
+  it('does not overwrite non-main CLAUDE.md on re-registration', () => {
+    simulateRegister('telegram_friends', false);
+    // User customizes the file
+    const mdPath = path.join(groupsDir, 'telegram_friends', 'CLAUDE.md');
+    fs.writeFileSync(mdPath, '# Custom\n\nUser-modified content.');
+    // Re-registering same folder as non-main
+    simulateRegister('telegram_friends', false);
+
+    const content = readGroupMd('telegram_friends');
     expect(content).toContain('User-modified content');
-    expect(content).not.toContain('Admin Context');
+  });
+
+  it('promotes non-main group to main when re-registered with isMain', () => {
+    // Initially registered as non-main (gets global template)
+    simulateRegister('telegram_main', false);
+    expect(readGroupMd('telegram_main')).not.toContain('Admin Context');
+
+    // User switches this channel to main
+    simulateRegister('telegram_main', true);
+    expect(readGroupMd('telegram_main')).toContain('Admin Context');
+  });
+
+  it('promotes across channels — WhatsApp non-main to Telegram main', () => {
+    // Start with WhatsApp as main, Telegram as non-main
+    simulateRegister('whatsapp_main', true);
+    simulateRegister('telegram_control', false);
+
+    expect(readGroupMd('whatsapp_main')).toContain('Admin Context');
+    expect(readGroupMd('telegram_control')).not.toContain('Admin Context');
+
+    // User decides Telegram should be the new main
+    simulateRegister('telegram_control', true);
+    expect(readGroupMd('telegram_control')).toContain('Admin Context');
+  });
+
+  it('promotion updates assistant name in promoted file', () => {
+    // Register as non-main with default name
+    simulateRegister('slack_ops', false);
+    expect(readGroupMd('slack_ops')).toContain('You are Andy');
+
+    // Promote to main with custom name
+    simulateRegister('slack_ops', true, 'Nova');
+    const content = readGroupMd('slack_ops');
+    expect(content).toContain('Admin Context');
+    expect(content).toContain('You are Nova');
+    expect(content).not.toContain('Andy');
   });
 
   it('handles missing templates gracefully', () => {

setup/register.ts

@@ -116,7 +116,7 @@ export async function run(args: string[]): Promise<void> {
     recursive: true,
   });
 
-  // Create CLAUDE.md in the new group folder from template if it doesn't exist.
+  // Create or upgrade CLAUDE.md in the group folder from the appropriate template.
   // The agent runs with CWD=/workspace/group and loads CLAUDE.md from there.
   const groupClaudeMdPath = path.join(
     projectRoot,
@@ -124,15 +124,30 @@ export async function run(args: string[]): Promise<void> {
     parsed.folder,
     'CLAUDE.md',
   );
-  if (!fs.existsSync(groupClaudeMdPath)) {
-    const templatePath = parsed.isMain
-      ? path.join(projectRoot, 'groups', 'main', 'CLAUDE.md')
-      : path.join(projectRoot, 'groups', 'global', 'CLAUDE.md');
+  const mainTemplatePath = path.join(projectRoot, 'groups', 'main', 'CLAUDE.md');
+  const globalTemplatePath = path.join(projectRoot, 'groups', 'global', 'CLAUDE.md');
+  const templatePath = parsed.isMain ? mainTemplatePath : globalTemplatePath;
+  const fileExists = fs.existsSync(groupClaudeMdPath);
+
+  // Promotion case: group was registered as non-main (got global template)
+  // and is now being re-registered as main. Replace with main template.
+  const needsPromotion =
+    parsed.isMain &&
+    fileExists &&
+    !fs.readFileSync(groupClaudeMdPath, 'utf-8').includes('## Admin Context');
+
+  if (!fileExists || needsPromotion) {
     if (fs.existsSync(templatePath)) {
       fs.copyFileSync(templatePath, groupClaudeMdPath);
       logger.info(
-        { file: groupClaudeMdPath, template: templatePath },
-        'Created CLAUDE.md from template',
+        {
+          file: groupClaudeMdPath,
+          template: templatePath,
+          promoted: needsPromotion,
+        },
+        needsPromotion
+          ? 'Promoted CLAUDE.md to main template'
+          : 'Created CLAUDE.md from template',
       );
     }
   }