feat(p10): archivage automatique des sessions terminées (rétention configurable)

- DB: migration #10 (sessions.archived_at + index), helpers archive/unarchive/archiveExpired (soft-archive, jamais de DELETE)
- core/retention-settings.ts: session_retention_days (défaut 30, 0=jamais, 1-3650) + session_purge_days (off)
- core/session-archive.ts: scheduler start/stop/sweep (calqué DiscoveryService), câblé dans runDaemon
- pty-manager.list({includeArchived}) + SessionSummary.archived + emitHistoricalUpdate
- routes: GET /sessions?includeArchived, POST/DELETE /sessions/:id/archive, POST /sessions/archive-now
- protocole additif: message WS session_archived (relayé par la gateway, abonnés 'sessions')
- settings: retentionDays/purgeDays exposés et validés dans PATCH /settings
- web: store sessions (showArchived + archive/unarchive), SessionsListView (toggle/badge/actions), SettingsView (slider rétention), i18n EN+FR
- tests: retention-settings + session-archive (vitest) + settings-routes étendu ; acceptance-p10.mjs (sweep, event WS, resume d'une session archivée → 201, rétention=0)

packages/server/test/session-archive.test.ts

@@ -0,0 +1,69 @@
+// Archivage automatique des sessions terminées (P10) : scheduler sweep() sur base :memory:.
+import { afterEach, beforeEach, describe, expect, it } from 'vitest';
+import { isSessionArchived, openDb, setSetting, type Db } from '../src/db/index.js';
+import { RETENTION_DAYS_KEY } from '../src/core/retention-settings.js';
+import { SessionArchiveService } from '../src/core/session-archive.js';
+
+let db: Db;
+
+function insertSession(id: string, endedAt: string | null): void {
+  db.prepare('INSERT INTO sessions (id, cwd, command, created_at, ended_at) VALUES (?, ?, ?, ?, ?)').run(
+    id,
+    '/tmp/x',
+    'bash',
+    '2020-01-01T00:00:00.000Z',
+    endedAt,
+  );
+}
+
+beforeEach(() => {
+  db = openDb(':memory:');
+  insertSession('old', '2020-01-01T00:00:00.000Z'); // terminée il y a longtemps
+  insertSession('recent', new Date().toISOString()); // terminée à l'instant
+  insertSession('live', null); // vivante (jamais archivée)
+});
+afterEach(() => db.close());
+
+describe('SessionArchiveService.sweep', () => {
+  it('archive seulement les sessions terminées plus anciennes que la rétention', () => {
+    setSetting(db, RETENTION_DAYS_KEY, '30');
+    const svc = new SessionArchiveService({ db });
+    const events: string[] = [];
+    svc.on('session_archived', (e) => events.push(e.id));
+
+    const n = svc.sweep();
+
+    expect(n).toBe(1);
+    expect(events).toEqual(['old']);
+    expect(isSessionArchived(db, 'old')).toBe(true);
+    expect(isSessionArchived(db, 'recent')).toBe(false);
+    expect(isSessionArchived(db, 'live')).toBe(false);
+  });
+
+  it('est idempotent : un second balayage n’archive rien de plus', () => {
+    setSetting(db, RETENTION_DAYS_KEY, '30');
+    const svc = new SessionArchiveService({ db });
+    expect(svc.sweep()).toBe(1);
+
+    const events: string[] = [];
+    svc.on('session_archived', (e) => events.push(e.id));
+    expect(svc.sweep()).toBe(0);
+    expect(events).toEqual([]);
+  });
+
+  it('rétention = 0 → no-op (archivage désactivé)', () => {
+    setSetting(db, RETENTION_DAYS_KEY, '0');
+    const svc = new SessionArchiveService({ db });
+    expect(svc.sweep()).toBe(0);
+    expect(isSessionArchived(db, 'old')).toBe(false);
+  });
+
+  it('start() déclenche un balayage immédiat puis stop() est sûr', () => {
+    setSetting(db, RETENTION_DAYS_KEY, '30');
+    const svc = new SessionArchiveService({ db, intervalMs: 60_000 });
+    svc.start();
+    expect(isSessionArchived(db, 'old')).toBe(true);
+    svc.stop();
+    svc.stop(); // idempotent
+  });
+});