feat(web): add prompt file read/write API

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

web/server/routes/prompts.ts

@@ -0,0 +1,45 @@
+import { Router } from 'express';
+import fs from 'fs';
+import path from 'path';
+
+const PROJECT_ROOT = path.resolve(__dirname, '..', '..', '..');
+
+export const promptsRouter = Router();
+
+const PROMPT_FILES: Record<string, string> = {
+  storyboard: 'prompts/分镜.md',
+  image: 'prompts/图片提示词.md',
+  video: 'prompts/视频提示词.md',
+};
+
+promptsRouter.get('/:accountId/:type', (req, res) => {
+  const { accountId, type } = req.params;
+  const relPath = PROMPT_FILES[type];
+  if (!relPath) return res.status(400).json({ error: 'Unknown type: ' + type });
+
+  const fullPath = path.join(PROJECT_ROOT, 'accounts', accountId, relPath);
+  if (!fs.existsSync(fullPath)) return res.status(404).json({ error: 'File not found' });
+
+  res.json({ path: relPath, content: fs.readFileSync(fullPath, 'utf-8') });
+});
+
+promptsRouter.put('/:accountId/:type', (req, res) => {
+  const { accountId, type } = req.params;
+  const { content } = req.body;
+  const relPath = PROMPT_FILES[type];
+  if (!relPath) return res.status(400).json({ error: 'Unknown type: ' + type });
+
+  const fullPath = path.join(PROJECT_ROOT, 'accounts', accountId, relPath);
+  const dir = path.dirname(fullPath);
+  if (!fs.existsSync(dir)) fs.mkdirSync(dir, { recursive: true });
+
+  fs.writeFileSync(fullPath, content, 'utf-8');
+  res.json({ ok: true });
+});
+
+promptsRouter.get('/:accountId', (req, res) => {
+  res.json(Object.keys(PROMPT_FILES).map((type) => ({
+    type,
+    path: PROMPT_FILES[type],
+  })));
+});