feat: socle BDD (tâche 1.9 Phase 1-2) + moteur APT (tâche 2 SJ-0→3) + WIP capabilities/auth/Rust

Checkpoint multi-chantiers (arbre vert : tsc 0 erreur, 70 tests, build OK).
- tâche 1.9 Phase 1 : schéma socle (machine_state/events/reports/raw_artifacts/
  hardware/metrics + colonnes étendues) + wiring refresh/execute. Migration 0002.
- tâche 1.9 Phase 2 : machine_credentials + machine_host_keys (non destructif,
  dual-read + backfill). Migration 0003. Fix séquence journal de migration.
- tâche 2 : SJ-0 (types étendus rétro-compatibles, réducteur Docker, resolveTemplate),
  SJ-1 (update-analyze enrichi), SJ-2 (apply + diff dpkg + timeout inactivité SSH),
  SJ-3 (reboot vérifié boot_id).
- WIP parallèle inclus : /api/capabilities, auth/apiTokens/apiClients, system metrics,
  scaffold app_rust, ajustements frontend.

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

server/services/system.ts

@@ -0,0 +1,44 @@
+// server/services/system.ts
+import os from "node:os";
+import type { SystemMetrics, SystemStatus } from "@shared/types.js";
+
+const APP_VERSION = "0.1.0";
+const MB = 1024 * 1024;
+
+function round2(value: number): number {
+  return Math.round(value * 100) / 100;
+}
+
+export function getSystemStatus(now = new Date()): SystemStatus {
+  return {
+    app: "system_update",
+    version: APP_VERSION,
+    apiVersion: "1",
+    serverTime: now.toISOString(),
+    uptimeSeconds: Math.round(process.uptime()),
+  };
+}
+
+export function getSystemMetrics(now = new Date()): SystemMetrics {
+  const memory = process.memoryUsage();
+  const load = os.loadavg();
+
+  return {
+    collectedAt: now.toISOString(),
+    process: {
+      uptimeSeconds: Math.round(process.uptime()),
+      rssMb: round2(memory.rss / MB),
+      heapUsedMb: round2(memory.heapUsed / MB),
+      heapTotalMb: round2(memory.heapTotal / MB),
+    },
+    host: {
+      loadAverage1m: round2(load[0] ?? 0),
+      loadAverage5m: round2(load[1] ?? 0),
+      loadAverage15m: round2(load[2] ?? 0),
+      totalMemoryMb: round2(os.totalmem() / MB),
+      freeMemoryMb: round2(os.freemem() / MB),
+    },
+  };
+}
+
+export const systemInternals = { round2 };