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/generate-videos.ts

@@ -0,0 +1,69 @@
+import path from 'path';
+import fs from 'fs';
+import { execSync } from 'child_process';
+import { runInit, loadJSON, PIPELINE_SCRIPT, PROJECT_ROOT } from './shared';
+import type { ToolDefinition } from './types';
+
+export const generateVideos: ToolDefinition = {
+  name: 'generate_videos',
+  description: '图生视频：根据已有图片和提示词生成 AI 视频。内部创建临时 manifest，先上传图片再执行 videos 阶段。返回视频文件路径。',
+  input_schema: {
+    type: 'object',
+    properties: {
+      accountId: { type: 'string', description: '账号ID，用于继承视频模型等配置' },
+      imagePath: { type: 'string', description: '图片文件路径（本地绝对路径或相对 PROJECTROOT 的路径）' },
+      prompt: { type: 'string', description: '视频提示词（videoPrompt），描述图片如何动起来' },
+      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' },
+      imagePrompt: { type: 'string', description: '图片提示词（可选），用于 manifest 记录' },
+    },
+    required: ['accountId', 'imagePath', 'prompt'],
+  },
+  execute: async (params) => {
+    const { accountId, imagePath, prompt, videoModel, imagePrompt } = params as Record<string, string>;
+    const resolvedImagePath = path.isAbsolute(imagePath)
+      ? imagePath
+      : path.resolve(PROJECT_ROOT, imagePath);
+    if (!fs.existsSync(resolvedImagePath)) {
+      return `错误: 图片文件不存在: ${resolvedImagePath}`;
+    }
+    const baseName = path.basename(resolvedImagePath);
+    const item = {
+      id: 1,
+      shotDesc: imagePrompt || prompt,
+      script: '',
+      imagePrompt: imagePrompt || prompt,
+      videoPrompt: prompt,
+      keyword: 'generated',
+      file: `images/${baseName}`,
+    };
+    const manifestPath = runInit({
+      account: accountId,
+      mode: 'single',
+      items: [item],
+      videoModel: videoModel,
+    });
+    // Copy image into manifest's images dir
+    const manifestDir = path.dirname(manifestPath);
+    const imagesDir = path.join(manifestDir, 'images');
+    if (!fs.existsSync(imagesDir)) fs.mkdirSync(imagesDir, { recursive: true });
+    const targetPath = path.join(imagesDir, baseName);
+    if (resolvedImagePath !== targetPath) {
+      fs.copyFileSync(resolvedImagePath, targetPath);
+    }
+    // Run upload + videos phases
+    execSync(`node "${PIPELINE_SCRIPT}" run --manifest "${manifestPath}" --phase upload,videos`, {
+      cwd: PROJECT_ROOT, encoding: 'utf-8',
+    });
+    const manifest = loadJSON(manifestPath) as {
+      items?: Array<{ id: number; video?: string; videoUrl?: string; videoDuration?: number; status?: string }>;
+    };
+    const results = (manifest.items || []).map((it) => ({
+      id: it.id,
+      video: it.video || null,
+      videoUrl: it.videoUrl || null,
+      videoDuration: it.videoDuration || null,
+      status: it.status,
+    }));
+    return JSON.stringify({ manifestPath, videos: results }, null, 2);
+  },
+};