feat: add SYNC_SYSTEM_NAMES env var to sync system names with hostname (#1917)

internal/hub/systems/system.go

@@ -279,6 +279,10 @@ func (sys *System) createRecords(data *system.CombinedData) (*core.Record, error
 			if err := createSystemDetailsRecord(txApp, data.Details, sys.Id); err != nil {
 				return err
 			}
+			// sync display name with hostname if enabled (details are fetched once per agent connection)
+			if syncNames, _ := utils.GetEnv("SYNC_SYSTEM_NAMES"); syncNames == "true" && data.Details.Hostname != "" {
+				systemRecord.Set("name", data.Details.Hostname)
+			}
 		}
 
 		if data.Monitors != nil {

internal/hub/systems/system_sync_name_test.go

@@ -0,0 +1,34 @@
+//go:build testing
+
+package systems
+
+import (
+	"testing"
+
+	"github.com/henrygd/beszel/internal/entities/system"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestCreateRecordsSyncSystemNames(t *testing.T) {
+	for _, tc := range []struct {
+		name     string
+		env      string
+		hostname string
+		expected string
+	}{
+		{"disabled", "", "new-host", "test-system"},
+		{"enabled", "true", "new-host", "new-host"},
+		{"enabled with empty hostname", "true", "", "test-system"},
+	} {
+		t.Run(tc.name, func(t *testing.T) {
+			t.Setenv("SYNC_SYSTEM_NAMES", tc.env)
+			sys, app := newTestSystemWithHub(t)
+			_, err := sys.createRecords(&system.CombinedData{Details: &system.Details{Hostname: tc.hostname}})
+			require.NoError(t, err)
+			record, err := app.FindRecordById("systems", sys.Id)
+			require.NoError(t, err)
+			assert.Equal(t, tc.expected, record.GetString("name"))
+		})
+	}
+}