fix: 任务列表忽略备份文件，避免同名重复任务

src/main/flows.ts

@@ -175,6 +175,7 @@ export function listFlows(): FlowSummary[] {
   const runs = latestRuns();
   for (const entry of fs.readdirSync(base)) {
     if (!entry.endsWith(".json")) continue;
+    if (/-pre-|\\.bak/i.test(entry)) continue;
     try {
       const flow = JSON.parse(fs.readFileSync(path.join(base, entry), "utf8")) as FlowDefinition;
       if (!flow?.id || !Array.isArray(flow.nodes)) continue;
@@ -231,3 +232,4 @@ export function deleteFlow(id: string): void {
   const target = fileOf(id);
   if (fs.existsSync(target)) fs.unlinkSync(target);
 }
+