feat(framework): P4 — upgrade-safe Constitution migration (both installers) (#590)

Co-authored-by: Jason Woltje <jason@diversecanvas.com>
Co-committed-by: Jason Woltje <jason@diversecanvas.com>

packages/mosaic/src/config/file-adapter.test.ts

@@ -99,11 +99,8 @@ describe('FileConfigAdapter.syncFramework — defaults seeding', () => {
     );
   });
 
-  it('preserves existing contract files — never overwrites user customization', async () => {
-    // Also plant a root-level AGENTS.md in sourceDir so that `syncDirectory`
-    // itself (not just the seed loop) has something to try to overwrite.
-    // Without this, the test would silently pass even if preserve semantics
-    // were broken in syncDirectory.
+  it('overwrites framework-owned files (backup-once) but preserves user-seeded files', async () => {
+    // Plant a root-level AGENTS.md in sourceDir so syncDirectory's preserve is exercised.
     writeFileSync(join(fixture.sourceDir, 'AGENTS.md'), '# shipped AGENTS from source root\n');
 
     writeFileSync(join(fixture.mosaicHome, 'TOOLS.md'), '# user-customized TOOLS\n');
@@ -112,18 +109,50 @@ describe('FileConfigAdapter.syncFramework — defaults seeding', () => {
     const adapter = new FileConfigAdapter(fixture.mosaicHome, fixture.sourceDir);
     await adapter.syncFramework('keep');
 
+    // User-seeded TOOLS.md is preserved.
     expect(readFileSync(join(fixture.mosaicHome, 'TOOLS.md'), 'utf-8')).toBe(
       '# user-customized TOOLS\n',
     );
-    expect(readFileSync(join(fixture.mosaicHome, 'AGENTS.md'), 'utf-8')).toBe(
+    // Framework-owned AGENTS.md is overwritten from defaults/ ...
+    expect(readFileSync(join(fixture.mosaicHome, 'AGENTS.md'), 'utf-8')).toBe('# AGENTS default\n');
+    // ... and the user's prior copy is backed up exactly once.
+    expect(readFileSync(join(fixture.mosaicHome, 'AGENTS.md.pre-constitution.bak'), 'utf-8')).toBe(
       '# user-customized AGENTS\n',
     );
-    // And the missing contract file still gets seeded.
+    // Framework-owned STANDARDS.md (absent) gets installed.
     expect(readFileSync(join(fixture.mosaicHome, 'STANDARDS.md'), 'utf-8')).toContain(
       '# STANDARDS default',
     );
   });
 
+  it('backs up a divergent framework-owned file only once (idempotent across re-sync)', async () => {
+    writeFileSync(join(fixture.mosaicHome, 'AGENTS.md'), '# user-customized AGENTS\n');
+    const adapter = new FileConfigAdapter(fixture.mosaicHome, fixture.sourceDir);
+
+    await adapter.syncFramework('keep'); // 1st: backup created, AGENTS overwritten
+    await adapter.syncFramework('keep'); // 2nd: AGENTS already == default, no new backup
+
+    expect(readFileSync(join(fixture.mosaicHome, 'AGENTS.md.pre-constitution.bak'), 'utf-8')).toBe(
+      '# user-customized AGENTS\n',
+    );
+  });
+
+  it('preserves SOUL.md and credentials through a framework-owned overwrite', async () => {
+    writeFileSync(join(fixture.mosaicHome, 'SOUL.md'), '# my persona\n');
+    writeFileSync(join(fixture.mosaicHome, 'AGENTS.md'), '# user-customized AGENTS\n');
+    mkdirSync(join(fixture.mosaicHome, 'credentials'), { recursive: true });
+    writeFileSync(join(fixture.mosaicHome, 'credentials', 'c.json'), 'token\n');
+
+    const adapter = new FileConfigAdapter(fixture.mosaicHome, fixture.sourceDir);
+    await adapter.syncFramework('keep');
+
+    expect(readFileSync(join(fixture.mosaicHome, 'SOUL.md'), 'utf-8')).toBe('# my persona\n');
+    expect(readFileSync(join(fixture.mosaicHome, 'credentials', 'c.json'), 'utf-8')).toBe(
+      'token\n',
+    );
+    expect(readFileSync(join(fixture.mosaicHome, 'AGENTS.md'), 'utf-8')).toBe('# AGENTS default\n');
+  });
+
   it('is a no-op for seeding when defaults/ dir does not exist', async () => {
     rmSync(fixture.defaultsDir, { recursive: true });
 

packages/mosaic/src/config/file-adapter.ts

@@ -13,12 +13,17 @@ import { join } from 'node:path';
  * This list must match the explicit seed loop in
  * packages/mosaic/framework/install.sh.
  */
-export const DEFAULT_SEED_FILES = [
-  'CONSTITUTION.md',
-  'AGENTS.md',
-  'STANDARDS.md',
-  'TOOLS.md',
-] as const;
+// Framework-owned contract files: re-copied from defaults/ on every upgrade (a
+// divergent existing copy is backed up once to <file>.pre-constitution.bak first).
+// MUST match FRAMEWORK_OWNED in packages/mosaic/framework/install.sh (append-friendly).
+export const FRAMEWORK_OWNED_FILES = ['CONSTITUTION.md', 'AGENTS.md', 'STANDARDS.md'] as const;
+
+// User-seeded contract files: written once on first install, then owned by the user.
+// MUST match USER_SEEDED in packages/mosaic/framework/install.sh.
+export const USER_SEEDED_FILES = ['TOOLS.md'] as const;
+
+// Union, retained for callers/tests that assert the full seed set on a fresh install.
+export const DEFAULT_SEED_FILES = [...FRAMEWORK_OWNED_FILES, ...USER_SEEDED_FILES] as const;
 import type { ConfigService, ConfigSection, ResolvedConfig } from './config-service.js';
 import type { SoulConfig, UserConfig, ToolsConfig, InstallAction } from '../types.js';
 import { soulSchema, userSchema, toolsSchema } from './schemas.js';
@@ -159,6 +164,7 @@ export class FileConfigAdapter implements ConfigService {
     const preservePaths =
       action === 'keep' || action === 'reconfigure'
         ? [
+            'CONSTITUTION.md',
             'AGENTS.md',
             'SOUL.md',
             'USER.md',
@@ -175,10 +181,10 @@ export class FileConfigAdapter implements ConfigService {
       excludeGit: true,
     });
 
-    // Copy framework-contract files (AGENTS.md, STANDARDS.md, TOOLS.md)
-    // from framework/defaults/ into the mosaic home root if they don't
-    // exist yet. These are written on first install only and are never
-    // overwritten afterwards — the user may have customized them.
+    // Reconcile framework-contract files from framework/defaults/ into the mosaic
+    // home root: framework-owned files (CONSTITUTION/AGENTS/STANDARDS) are overwritten
+    // every upgrade (backup-once); user-seeded files (TOOLS) are written on first
+    // install only. Mirrors reconcile_framework_files() in install.sh.
     //
     // SOUL.md and USER.md are deliberately NOT seeded here. They are
     // generated from templates by the soul/user wizard stages with
@@ -186,7 +192,20 @@ export class FileConfigAdapter implements ConfigService {
     // identity flow and leak placeholder content into the mosaic home.
     const defaultsDir = join(this.sourceDir, 'defaults');
     if (existsSync(defaultsDir)) {
-      for (const entry of DEFAULT_SEED_FILES) {
+      // Framework-owned: overwrite from defaults/ every sync; back up a divergent
+      // existing copy ONCE to <file>.pre-constitution.bak before the first overwrite.
+      for (const entry of FRAMEWORK_OWNED_FILES) {
+        const src = join(defaultsDir, entry);
+        const dest = join(this.mosaicHome, entry);
+        if (!existsSync(src) || !statSync(src).isFile()) continue;
+        const bak = `${dest}.pre-constitution.bak`;
+        if (existsSync(dest) && !readFileSync(src).equals(readFileSync(dest)) && !existsSync(bak)) {
+          copyFileSync(dest, bak);
+        }
+        copyFileSync(src, dest);
+      }
+      // User-seeded: write only if absent.
+      for (const entry of USER_SEEDED_FILES) {
         const src = join(defaultsDir, entry);
         const dest = join(this.mosaicHome, entry);
         if (existsSync(dest)) continue;