task 1: 自动保存(30s) — 新增autoSaveTimer每30秒静默保存草稿

frontend/src/views/MapCanvas.vue

@@ -708,6 +708,7 @@ async function deleteNode(dimKey: string, oi: number) {
 
 // ── 保存 ──
 let saveTimer: ReturnType<typeof setTimeout> | null = null
+let autoSaveTimer: ReturnType<typeof setInterval> | null = null
 let isSaving = false
 
 function debouncedSaveCanvas() {
@@ -716,7 +717,7 @@ function debouncedSaveCanvas() {
   saveTimer = setTimeout(() => { saveCanvas() }, 500)
 }
 
-async function saveCanvas() {
+async function saveCanvas(silent?: boolean) {
   if (!selectedMap.value) return
   if (isSaving) return
   isSaving = true
@@ -730,7 +731,7 @@ async function saveCanvas() {
       canvas_data: { connections: connections.value },
       version_num: currentMap.value?.version_num,
     })
-    ElMessage.success("已保存")
+    if (!silent) ElMessage.success("已保存")
   } catch (e: any) {
     if (e?.response?.status === 409) {
       ElMessage.warning("地图已被修改，刷新后重试")
@@ -927,12 +928,17 @@ onMounted(async () => {
   for (const kpi of allKpis.value) {
     if (kpi.kpi_code) kpiNameMap[kpi.kpi_code] = kpi.kpi_name || kpi.kpi_code
   }
+  // 自动保存：每30秒自动保存草稿
+  autoSaveTimer = setInterval(() => {
+    if (currentMap?.status === 'draft') saveCanvas(true)
+  }, 30000)
   window.addEventListener('resize', triggerRecalc)
 })
 
 onUnmounted(() => {
   window.removeEventListener('resize', triggerRecalc)
   if (saveTimer) clearTimeout(saveTimer)
+  if (autoSaveTimer) clearInterval(autoSaveTimer)
 })
 </script>