fix(update): re-seed framework on version drift, not just in-command updates (#642)

`mosaic update` only re-seeded ~/.config/mosaic when the @mosaicstack/mosaic
package was upgraded *within that same command*. When the CLI is upgraded
another way — a direct `npm i -g @mosaicstack/mosaic`, or an update run where
only sibling packages were outdated — the framework files (launchers, runtime
adapters, fleet tools) silently stayed stale, so shipped fixes never activated.
Critically, the "all packages up to date" branch returned before any re-seed
could run, so a drifted-but-current host had no path to reconcile.

Add framework drift detection: compare the on-disk schema version
(~/.config/mosaic/.framework-version) against the version bundled in the
installed package (FRAMEWORK_VERSION in the bundled install.sh). `mosaic update`
now re-seeds when the mosaic package updated OR the on-disk framework is older
than bundled — including from the up-to-date branch. Detection is conservative:
if either version can't be read it reports no drift, so a missing/unreadable
version file never triggers an unexpected re-seed. `--no-reseed` still opts out.

The re-seed + unit-refresh + relaunch sequence is factored into a single local
helper shared by both the post-update and drift paths (no behavior change to the
existing path beyond also firing on drift).

New exported, unit-tested helpers in update-checker.ts:
- readInstalledFrameworkVersion / readBundledFrameworkVersion
- checkFrameworkDrift -> { drifted, installed, bundled }

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

packages/mosaic/src/cli.ts

@@ -30,6 +30,7 @@ import {
   refreshActiveFleetUnits,
   readRosterAgentNames,
   buildRelaunchCommands,
+  checkFrameworkDrift,
   FRAMEWORK_RESEED_PACKAGE,
 } from './runtime/update-checker.js';
 import { runWizard } from './wizard.js';
@@ -418,6 +419,48 @@ program
     // checkForAllUpdates imported statically above
     const { execSync } = await import('node:child_process');
 
+    // Re-seed the framework from the freshly-installed package, propagate shipped
+    // systemd unit fixes to the active units, and (opt-in) relaunch durable
+    // agents. Shared by the "packages updated" and the "framework drift" paths.
+    const reseedFramework = (reason: string): void => {
+      console.log(reason);
+      const reseed = runFrameworkReseed();
+      if (!reseed.ok) {
+        console.error(
+          `\n⚠ Framework re-seed skipped: ${reseed.reason ?? 'unknown'}.\n` +
+            '  Activate manually: bash "$(npm root -g)/@mosaicstack/mosaic/framework/install.sh" ' +
+            '(MOSAIC_SYNC_ONLY=1 MOSAIC_INSTALL_MODE=keep)',
+        );
+        return;
+      }
+      console.log('✔ Framework re-seeded.');
+      // Propagate shipped systemd unit fixes to the ACTIVE units (re-seed only
+      // touches ~/.config/mosaic/systemd/user; systemd runs ~/.config/systemd/user).
+      const units = refreshActiveFleetUnits();
+      if (units.refreshed.length > 0) {
+        console.log(`✔ Refreshed ${units.refreshed.length} active systemd unit(s).`);
+      }
+      const agents = readRosterAgentNames();
+      if (agents.length === 0) return;
+      if (opts.relaunch) {
+        console.log(`\nRelaunching ${agents.length} fleet agent(s) to pick up the new runtime…`);
+        for (const restart of buildRelaunchCommands(agents)) {
+          try {
+            execSync(restart.join(' '), { stdio: 'inherit', timeout: 30_000 });
+          } catch {
+            console.error(`  ⚠ failed to restart agent — run: ${restart.join(' ')}`);
+          }
+        }
+        console.log('✔ Agents relaunched.');
+      } else {
+        console.log(
+          `\nℹ ${agents.length} fleet agent(s) are still running the previous runtime. ` +
+            'Restart them to activate the update:\n    mosaic update --relaunch   ' +
+            '(or: mosaic fleet restart <agent>)',
+        );
+      }
+    };
+
     console.log('Checking for updates…');
     const results = checkForAllUpdates({ skipCache: true });
 
@@ -432,6 +475,18 @@ program
         process.exit(1);
       }
       console.log('\n✔ All packages up to date.');
+      // #642: the CLI may have been upgraded outside `mosaic update` (e.g. a
+      // direct `npm i -g`), leaving the framework files stale even though no
+      // package is reported outdated. Detect that via the framework version and
+      // re-seed so shipped launcher/runtime fixes still activate.
+      const drift = checkFrameworkDrift();
+      if (drift.drifted && opts.reseed !== false) {
+        reseedFramework(
+          `\nFramework drift detected (on-disk v${drift.installed} < bundled v${drift.bundled}) — ` +
+            'the CLI was updated outside `mosaic update`. Re-seeding framework files into ' +
+            '~/.config/mosaic (data-safe; keeps your edits)…',
+        );
+      }
       return;
     }
 
@@ -456,52 +511,17 @@ program
     // F3-m3 / R13: the CLI is updated, but the framework files in
     // ~/.config/mosaic/ are still the previous version. Re-seed them from the
     // freshly-installed package so shipped launcher/runtime changes ACTIVATE.
-    // Only when the framework-bearing package itself updated.
+    // Re-seed when the framework-bearing package itself updated OR the on-disk
+    // framework is older than the freshly-installed one (#642 — e.g. only
+    // sibling packages were outdated but the CLI was already ahead).
     const mosaicUpdated = outdated.some(
       (r: { package: string }) => r.package === FRAMEWORK_RESEED_PACKAGE,
     );
-    if (mosaicUpdated && opts.reseed !== false) {
-      console.log(
+    const drift = checkFrameworkDrift();
+    if ((mosaicUpdated || drift.drifted) && opts.reseed !== false) {
+      reseedFramework(
         '\nRe-seeding framework files into ~/.config/mosaic (data-safe; keeps your edits)…',
       );
-      const reseed = runFrameworkReseed();
-      if (reseed.ok) {
-        console.log('✔ Framework re-seeded.');
-        // Propagate shipped systemd unit fixes to the ACTIVE units (re-seed only
-        // touches ~/.config/mosaic/systemd/user; systemd runs ~/.config/systemd/user).
-        const units = refreshActiveFleetUnits();
-        if (units.refreshed.length > 0) {
-          console.log(`✔ Refreshed ${units.refreshed.length} active systemd unit(s).`);
-        }
-        const agents = readRosterAgentNames();
-        if (agents.length > 0) {
-          if (opts.relaunch) {
-            console.log(
-              `\nRelaunching ${agents.length} fleet agent(s) to pick up the new runtime…`,
-            );
-            for (const restart of buildRelaunchCommands(agents)) {
-              try {
-                execSync(restart.join(' '), { stdio: 'inherit', timeout: 30_000 });
-              } catch {
-                console.error(`  ⚠ failed to restart agent — run: ${restart.join(' ')}`);
-              }
-            }
-            console.log('✔ Agents relaunched.');
-          } else {
-            console.log(
-              `\nℹ ${agents.length} fleet agent(s) are still running the previous runtime. ` +
-                'Restart them to activate the update:\n    mosaic update --relaunch   ' +
-                '(or: mosaic fleet restart <agent>)',
-            );
-          }
-        }
-      } else {
-        console.error(
-          `\n⚠ Framework re-seed skipped: ${reseed.reason ?? 'unknown'}.\n` +
-            '  Activate manually: bash "$(npm root -g)/@mosaicstack/mosaic/framework/install.sh" ' +
-            '(MOSAIC_SYNC_ONLY=1 MOSAIC_INSTALL_MODE=keep)',
-        );
-      }
     }
   });
 

packages/mosaic/src/runtime/update-checker.reseed.spec.ts

@@ -8,6 +8,9 @@ import {
   readRosterAgentNames,
   runFrameworkReseed,
   refreshActiveFleetUnits,
+  readInstalledFrameworkVersion,
+  readBundledFrameworkVersion,
+  checkFrameworkDrift,
 } from './update-checker.js';
 import { existsSync, readFileSync } from 'node:fs';
 
@@ -123,3 +126,73 @@ describe('refreshActiveFleetUnits', () => {
     expect(existsSync(join(configHome, 'systemd', 'user', 'mosaic-agent@.service'))).toBe(false);
   });
 });
+
+/**
+ * #642: re-seed when the on-disk framework is older than the bundled one even
+ * if no package is reported outdated (CLI upgraded outside `mosaic update`).
+ */
+describe('framework drift detection', () => {
+  let home: string; // stand-in for ~/.config/mosaic
+  let fw: string; // stand-in for the bundled framework root
+
+  beforeEach(() => {
+    const root = mkdtempSync(join(tmpdir(), 'mosaic-drift-'));
+    home = join(root, 'mosaic');
+    fw = join(root, 'framework');
+    mkdirSync(home, { recursive: true });
+    mkdirSync(fw, { recursive: true });
+  });
+  afterEach(() => {
+    rmSync(join(home, '..'), { recursive: true, force: true });
+  });
+
+  const writeInstalled = (v: string) => writeFileSync(join(home, '.framework-version'), v);
+  const writeBundled = (v: string) =>
+    writeFileSync(join(fw, 'install.sh'), `#!/usr/bin/env bash\nFRAMEWORK_VERSION=${v}\n`);
+
+  describe('readInstalledFrameworkVersion', () => {
+    it('returns undefined when the version file is absent', () => {
+      expect(readInstalledFrameworkVersion(home)).toBeUndefined();
+    });
+    it('parses the integer (tolerating surrounding whitespace)', () => {
+      writeInstalled('  3\n');
+      expect(readInstalledFrameworkVersion(home)).toBe(3);
+    });
+    it('returns undefined for non-numeric content', () => {
+      writeInstalled('not-a-number\n');
+      expect(readInstalledFrameworkVersion(home)).toBeUndefined();
+    });
+  });
+
+  describe('readBundledFrameworkVersion', () => {
+    it('returns undefined when install.sh is absent', () => {
+      expect(readBundledFrameworkVersion(fw)).toBeUndefined();
+    });
+    it('parses FRAMEWORK_VERSION=<n> from install.sh', () => {
+      writeBundled('4');
+      expect(readBundledFrameworkVersion(fw)).toBe(4);
+    });
+  });
+
+  describe('checkFrameworkDrift', () => {
+    it('reports drift when on-disk is older than bundled', () => {
+      writeInstalled('3');
+      writeBundled('4');
+      expect(checkFrameworkDrift(home, fw)).toEqual({ drifted: true, installed: 3, bundled: 4 });
+    });
+    it('no drift when versions match', () => {
+      writeInstalled('4');
+      writeBundled('4');
+      expect(checkFrameworkDrift(home, fw)).toMatchObject({ drifted: false });
+    });
+    it('no drift when on-disk is newer than bundled', () => {
+      writeInstalled('5');
+      writeBundled('4');
+      expect(checkFrameworkDrift(home, fw)).toMatchObject({ drifted: false });
+    });
+    it('no drift (conservative) when a version cannot be read', () => {
+      writeBundled('4'); // installed version file missing
+      expect(checkFrameworkDrift(home, fw)).toMatchObject({ drifted: false, bundled: 4 });
+    });
+  });
+});

packages/mosaic/src/runtime/update-checker.ts

@@ -521,6 +521,75 @@ export function runFrameworkReseed(
   }
 }
 
+// ─── Framework drift detection (#642) ────────────────────────────────────────
+//
+// `mosaic update` only re-seeds the framework when the @mosaicstack/mosaic
+// package itself is upgraded *within that command*. When the CLI is upgraded
+// some OTHER way — a direct `npm i -g @mosaicstack/mosaic`, or an upgrade run
+// where only sibling packages were outdated — the framework files in
+// ~/.config/mosaic stay stale and shipped launcher/runtime fixes never
+// activate. Comparing the on-disk framework schema version against the version
+// bundled in the installed package detects exactly that situation.
+
+/** Read the framework schema version recorded on disk (~/.config/mosaic/.framework-version). */
+export function readInstalledFrameworkVersion(
+  mosaicHome = join(homedir(), '.config', 'mosaic'),
+): number | undefined {
+  const vf = join(mosaicHome, '.framework-version');
+  if (!existsSync(vf)) return undefined;
+  try {
+    const n = parseInt(readFileSync(vf, 'utf-8').trim(), 10);
+    return Number.isFinite(n) ? n : undefined;
+  } catch {
+    return undefined;
+  }
+}
+
+/**
+ * Read the framework schema version shipped in the installed package by parsing
+ * `FRAMEWORK_VERSION=<n>` out of the bundled install.sh (the authoritative
+ * source the installer writes to .framework-version).
+ */
+export function readBundledFrameworkVersion(
+  frameworkRoot = resolveBundledFrameworkRoot(),
+): number | undefined {
+  const installer = join(frameworkRoot, 'install.sh');
+  if (!existsSync(installer)) return undefined;
+  try {
+    const m = readFileSync(installer, 'utf-8').match(/^\s*FRAMEWORK_VERSION=(\d+)/m);
+    const raw = m?.[1];
+    if (!raw) return undefined;
+    const n = parseInt(raw, 10);
+    return Number.isFinite(n) ? n : undefined;
+  } catch {
+    return undefined;
+  }
+}
+
+export interface FrameworkDrift {
+  /** True only when both versions are known AND the on-disk one is older. */
+  drifted: boolean;
+  installed?: number;
+  bundled?: number;
+}
+
+/**
+ * Detect whether the on-disk framework is older than the framework bundled in
+ * the installed CLI (#642). Conservative: if either version can't be read the
+ * result is no-drift, so a missing/unreadable version file never triggers an
+ * unexpected re-seed.
+ */
+export function checkFrameworkDrift(
+  mosaicHome = join(homedir(), '.config', 'mosaic'),
+  frameworkRoot = resolveBundledFrameworkRoot(),
+): FrameworkDrift {
+  const installed = readInstalledFrameworkVersion(mosaicHome);
+  const bundled = readBundledFrameworkVersion(frameworkRoot);
+  const drifted =
+    typeof installed === 'number' && typeof bundled === 'number' && installed < bundled;
+  return { drifted, installed, bundled };
+}
+
 /**
  * Best-effort parse of the fleet roster for agent names (used to relaunch
  * durable agents after a re-seed). Returns [] when no roster exists.