feat(server/stats): stats-overhaul Phase2 — 每设备归因 + GB 综合配额

服务端记账从「账户」细到「每设备」(每设备独立 dp_uuid),配额单位分钟→GB
按账户综合卡控。000015_per_device_usage 迁移(mysql+sqlite 双份):devices.dp_uuid
+ usage_device_daily 表 + plans.daily_mb。handler_grpc 按 dp_uuid 回映射
(user_id,device_id) 双写账户+每设备;usage 服务/handler 暴露 /v1/usage(/devices)。
含 sqlite_per_device / usage handler 测试。

注:此迁移 prod 已 migrate up 运行、部署二进制已内嵌;本次补提交使 git 与线上一致。

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

server/internal/nodes/grpc_test.go

@@ -37,6 +37,9 @@ type mockNodeStore struct {
 	configVer     int64
 	usageAccum    []mockUsageEntry
 	usersByDpUUID map[string]int64
+	// devicesByDpUUID maps a per-device dp_uuid → {userID, deviceID}.
+	devicesByDpUUID  map[string][2]int64
+	deviceUsageAccum []mockDeviceUsageEntry
 }
 
 type mockUsageEntry struct {
@@ -47,6 +50,15 @@ type mockUsageEntry struct {
 	Minutes   int64
 }
 
+type mockDeviceUsageEntry struct {
+	UserID    int64
+	DeviceID  int64
+	Date      time.Time
+	BytesUp   int64
+	BytesDown int64
+	Minutes   int64
+}
+
 func (m *mockNodeStore) NodeByUUID(_ context.Context, uuid string) (*nodes.NodeRow, error) {
 	if uuid == m.nodeUUID {
 		return &nodes.NodeRow{
@@ -105,6 +117,44 @@ func (m *mockNodeStore) AccumulateUsage(_ context.Context, userID int64, date ti
 	return nil
 }
 
+func (m *mockNodeStore) EnsureDeviceDpUUID(_ context.Context, _ int64, _ string) (string, int64, error) {
+	return "", 0, nil
+}
+
+func (m *mockNodeStore) AccountDayBytes(_ context.Context, _ int64, _ time.Time) (int64, error) {
+	return 0, nil
+}
+
+func (m *mockNodeStore) UserDeviceByDpUUID(_ context.Context, dpUUID string) (int64, int64, bool, error) {
+	if m.devicesByDpUUID != nil {
+		if ud, ok := m.devicesByDpUUID[dpUUID]; ok {
+			return ud[0], ud[1], true, nil
+		}
+	}
+	if uid, ok := m.usersByDpUUID[dpUUID]; ok {
+		return uid, 0, true, nil // legacy account credential, no device dimension
+	}
+	return 0, 0, false, nil
+}
+
+func (m *mockNodeStore) AccumulateDeviceUsage(_ context.Context, userID, deviceID int64, date time.Time,
+	bytesUp, bytesDown, minutes int64,
+) error {
+	m.mu.Lock()
+	defer m.mu.Unlock()
+	m.deviceUsageAccum = append(m.deviceUsageAccum,
+		mockDeviceUsageEntry{userID, deviceID, date, bytesUp, bytesDown, minutes})
+	return nil
+}
+
+func (m *mockNodeStore) deviceUsageLog() []mockDeviceUsageEntry {
+	m.mu.Lock()
+	defer m.mu.Unlock()
+	out := make([]mockDeviceUsageEntry, len(m.deviceUsageAccum))
+	copy(out, m.deviceUsageAccum)
+	return out
+}
+
 func (m *mockNodeStore) usageLog() []mockUsageEntry {
 	m.mu.Lock()
 	defer m.mu.Unlock()
@@ -850,4 +900,51 @@ func TestReportUsage_Accumulates(t *testing.T) {
 		t.Errorf("bytes_up=%d bytes_down=%d, want 100/200",
 			log[0].BytesUp, log[0].BytesDown)
 	}
+	// Account-level dp_uuid → no per-device attribution (deviceID 0).
+	if dev := b.store.deviceUsageLog(); len(dev) != 0 {
+		t.Errorf("device usage should be empty for account credential, got %d", len(dev))
+	}
+}
+
+// TestReportUsage_PerDevice verifies a per-device dp_uuid is dual-written: account
+// rollup (usage_daily) AND per-device attribution (usage_device_daily).
+func TestReportUsage_PerDevice(t *testing.T) {
+	const nodeUUID = "test-node-usage-dev"
+	b := newTestServer(t, 1, nodeUUID)
+	ctx := context.Background()
+	// dp-dev1 resolves to user 101, device 55 (per-device credential).
+	b.store.devicesByDpUUID = map[string][2]int64{"dp-dev1": {101, 55}}
+
+	_, _, conn := enrollNode(t, b, nodeUUID)
+	client := agentv1.NewAgentServiceClient(conn)
+	if _, err := client.Register(ctx, &agentv1.RegisterRequest{NodeUUID: nodeUUID}); err != nil {
+		t.Fatalf("Register: %v", err)
+	}
+
+	now := time.Now()
+	if _, err := client.ReportUsage(ctx, &agentv1.UsageReport{
+		NodeUUID:        nodeUUID,
+		WindowStartUnix: now.Add(-time.Minute).Unix(),
+		WindowEndUnix:   now.Unix(),
+		Entries: []*agentv1.UsageEntry{
+			{DpUUID: "dp-dev1", BytesUp: 100, BytesDown: 200, SessionMinutes: 3},
+		},
+	}); err != nil {
+		t.Fatalf("ReportUsage: %v", err)
+	}
+
+	// Account rollup still recorded.
+	acc := b.store.usageLog()
+	if len(acc) != 1 || acc[0].UserID != 101 || acc[0].BytesUp != 100 {
+		t.Fatalf("account usage wrong: %+v", acc)
+	}
+	// Per-device usage recorded with device attribution.
+	dev := b.store.deviceUsageLog()
+	if len(dev) != 1 {
+		t.Fatalf("device usage has %d entries, want 1", len(dev))
+	}
+	if dev[0].UserID != 101 || dev[0].DeviceID != 55 ||
+		dev[0].BytesUp != 100 || dev[0].BytesDown != 200 || dev[0].Minutes != 3 {
+		t.Errorf("device usage wrong: %+v", dev[0])
+	}
 }