feat(定时任务): 内置「模板数据转换器」按 HTML 模板填充 JSON 生成大屏

- 模板填充引擎 template_fill.py：模板注册表 + schema 骨架 + 结构校验 + 行级安全填充；
  模板自带 DATA 即 schema 来源。no.1 可转换填充（含 MANIFEST 更新时间刷新），
  no.2 暂为「只展示」(convertible=False) 原样输出已有数据
- 内置 agent template-json-builder（seed + SOUL），随 lifespan 注入，自动出现在
  定时任务「执行智能体」下拉
- 调度器新增模板填充执行分支 _run_template_fill_attempt：源 JSON→大模型转换→
  结构校验→失败回喂重试；空源/只展示模板直接用模板默认数据，绝不失败
- API：GET /api/scheduled-tasks/html-templates
- 前端：选中该 agent 后条件渲染「HTML模板」下拉 + .json 上传，只展示型模板隐藏 JSON 输入
- 文档同步（前后端 CLAUDE.md）

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

frontend-web/src/strategy-components/components/task-components/TaskJumpBar.tsx

@@ -10,6 +10,7 @@
 import { useEffect, useMemo, useState } from "react";
 import { useNavigate } from "react-router-dom";
 import {
+  ArrowLeft,
   ArrowRight,
   ExternalLink,
   FileSearch,
@@ -95,16 +96,27 @@ export function TaskJumpBar({
     });
   };
 
-  const nextButtons = jumpButtons.filter(isNextTaskButton);
-  const menuButtons = jumpButtons.filter((btn) => !isNextTaskButton(btn));
+  // 底部栏只放「上一步 / 下一步」：prev 组渲染在 next 组之前 → 视觉上「上一步」在「下一步」左边
+  // （容器 justify-end 右对齐，数组先后即左右先后）。其余按钮进右侧悬浮菜单。
+  const prevButtons = jumpButtons.filter(isPrevTaskButton);
+  const nextButtons = jumpButtons.filter((btn) => isNextTaskButton(btn) && !isPrevTaskButton(btn));
+  const barButtons = [...prevButtons, ...nextButtons];
+  const menuButtons = jumpButtons.filter(
+    (btn) => !isNextTaskButton(btn) && !isPrevTaskButton(btn),
+  );
 
   return (
     <>
       {menuButtons.length > 0 && <TaskSideJumpMenu buttons={menuButtons} onRun={handleRun} />}
-      {nextButtons.length > 0 && (
+      {barButtons.length > 0 && (
         <div className="border-border/70 bg-background/90 flex shrink-0 flex-wrap items-center justify-end gap-3 border-t px-5 py-3 backdrop-blur-xl dark:border-[#1b477e]/70 dark:bg-[#061b35]/85">
-          {nextButtons.map((btn) => (
-            <TaskJumpButton key={btn.id} button={btn} onRun={handleRun} />
+          {barButtons.map((btn) => (
+            <TaskJumpButton
+              key={btn.id}
+              button={btn}
+              onRun={handleRun}
+              variant={isPrevTaskButton(btn) ? "secondary" : "primary"}
+            />
           ))}
         </div>
       )}
@@ -122,21 +134,35 @@ function isNextTaskButton(btn: TaskButton) {
   return btn.id.toLowerCase().includes("next") || btn.label.trim() === "下一步";
 }
 
+/** 「上一步」按钮：id 含 prev 或文案为「上一步」——底部栏里渲染到「下一步」左边。 */
+function isPrevTaskButton(btn: TaskButton) {
+  return btn.id.toLowerCase().includes("prev") || btn.label.trim() === "上一步";
+}
+
 function TaskJumpButton({
   button,
   onRun,
+  variant = "primary",
 }: {
   button: TaskButton;
   onRun: (button: TaskButton) => void;
+  /** primary=下一步（实心主色）/ secondary=上一步（描边次要，置于下一步左侧）。 */
+  variant?: "primary" | "secondary";
 }) {
+  const styles =
+    variant === "secondary"
+      ? "border-[var(--color-main)]/40 bg-transparent text-[var(--color-main)] hover:bg-[var(--color-main)]/10 dark:text-[#7eb6ff] dark:border-[#7eb6ff]/40 dark:hover:bg-[#7eb6ff]/10"
+      : "border-transparent bg-[var(--color-main)] text-white shadow-sm hover:bg-[var(--brand-950)]";
   return (
     <Button
-      className="h-11 gap-2 border-transparent bg-[var(--color-main)] px-6 text-base text-white shadow-sm hover:bg-[var(--brand-950)]"
+      variant={variant === "secondary" ? "outline" : "default"}
+      className={cn("h-11 gap-2 px-6 text-base", styles)}
       onClick={() => onRun(button)}
       title={desensitize(button.label)}
     >
+      {variant === "secondary" && <ArrowLeft className="h-5 w-5 shrink-0" />}
       <span className="truncate">{desensitize(button.label)}</span>
-      {renderTaskJumpIcon(button, "h-5 w-5 shrink-0")}
+      {variant === "primary" && renderTaskJumpIcon(button, "h-5 w-5 shrink-0")}
     </Button>
   );
 }