refactor(agent): 将 tools 模块拆分为独立文件并优化导入路径

将 `tools.ts` 拆分为按功能划分的独立文件，并存放于 `tools/` 目录下，同时更新导入路径；优化 agent 系统提示语，移除冗余的「美图 Agent」前缀。

web/server/agent/tools/create-manifest.ts

@@ -0,0 +1,50 @@
+import path from 'path';
+import os from 'os';
+import fs from 'fs';
+import { execSync } from 'child_process';
+import { PIPELINE_SCRIPT, PROJECT_ROOT } from './shared';
+import type { ToolDefinition } from './types';
+
+export const createManifest: ToolDefinition = {
+  name: 'create_manifest',
+  description: '初始化新的 manifest.json，调用 pipeline.js init 创建输出目录和项目骨架。这是视频创作 pipeline 的起点。',
+  input_schema: {
+    type: 'object',
+    properties: {
+      accountId: { type: 'string', description: '账号ID，决定模型、参考图等配置来源' },
+      mode: { type: 'string', description: '创作模式: single (单图模式) 或 framePair (首尾帧模式)' },
+      items: { type: 'string', description: '分镜数据 JSON 数组字符串。每个元素需包含 shotDesc (分镜描述) 和 script (旁白文案)，可选 imagePrompt、videoPrompt、directorRef、keyword、duration' },
+      imageModel: { type: 'string', description: '生图模型（可选，默认继承账号配置）: gemini, mj, gpt-image, kling' },
+      videoModel: { type: 'string', description: '视频模型（可选，默认继承账号配置）: veo3-fast, veo3-fast-frames, kling, grok' },
+      format: { type: 'string', description: '画幅（可选，默认继承账号配置）: 9:16, 16:9, 1:1' },
+    },
+    required: ['accountId', 'mode', 'items'],
+  },
+  execute: async (params) => {
+    const { accountId, mode, items, imageModel, videoModel, format } = params as Record<string, string>;
+    // Validate items JSON
+    let parsed: unknown;
+    try { parsed = JSON.parse(items); } catch { return '错误: items 不是合法的 JSON 字符串'; }
+    if (!Array.isArray(parsed) || (parsed as unknown[]).length === 0) return '错误: items 必须是非空 JSON 数组';
+    // Write items to temp file to avoid shell escaping issues
+    const tmpFile = path.join(os.tmpdir(), `pipeline-items-${Date.now()}.json`);
+    fs.writeFileSync(tmpFile, items, 'utf-8');
+    try {
+      const args = [
+        `"${PIPELINE_SCRIPT}"`, 'init',
+        `--account "${accountId}"`,
+        `--mode ${mode}`,
+        `--items-file "${tmpFile}"`,
+        imageModel ? `--image-model ${imageModel}` : '',
+        videoModel ? `--video-model ${videoModel}` : '',
+        format ? `--format ${format}` : '',
+      ].filter(Boolean).join(' ');
+      const output = execSync(`node ${args}`, { cwd: PROJECT_ROOT, encoding: 'utf-8' });
+      const match = output.match(/Manifest 已创建: (.+)/);
+      const manifestPath = match ? match[1].trim() : '(unable to parse path)';
+      return `Manifest 已创建: ${manifestPath}\n\n${output}`;
+    } finally {
+      try { fs.unlinkSync(tmpFile); } catch { /* ignore */ }
+    }
+  },
+};