fix: 修复预览与 PDF 渲染边界问题

apps/server/src/app.ts

@@ -8,7 +8,11 @@ import {
   exportConfigSchema,
   supportedPaperFormats
 } from "@md-to-pdf/core";
-import { RENDERER_VERSION, renderMarkdown } from "@md-to-pdf/renderer";
+import {
+  MarkdownDocumentParseError,
+  RENDERER_VERSION,
+  renderMarkdown
+} from "@md-to-pdf/renderer";
 import {
   createPdfGenerator,
   PdfEngineClosedError,
@@ -66,6 +70,29 @@ function validateMarkdownRequest(
   };
 }
 
+function renderMarkdownRequest(
+  markdown: string,
+  language: string | undefined
+) {
+  try {
+    return {
+      success: true as const,
+      document: renderMarkdown(markdown, {
+        ...(language ? { language } : {})
+      })
+    };
+  } catch (error) {
+    if (error instanceof MarkdownDocumentParseError) {
+      return {
+        success: false as const,
+        error: error.code,
+        message: error.message
+      };
+    }
+    throw error;
+  }
+}
+
 function encodeRfc5987(value: string) {
   return encodeURIComponent(value).replace(
     /[!'()*]/g,
@@ -142,7 +169,8 @@ export function buildApp(options: BuildAppOptions = {}) {
   const themes = createThemeRegistry({
     bundledRoot: resolve(projectRoot, "themes"),
     localRoot:
-      options.localThemeRoot ?? resolve(projectRoot, ".local", "themes")
+      options.localThemeRoot ?? resolve(projectRoot, ".local", "themes"),
+    onWarning: (message) => app.log.warn(message)
   });
   const pdfGenerator =
     options.pdfGenerator ?? createPdfGenerator();
@@ -254,9 +282,17 @@ export function buildApp(options: BuildAppOptions = {}) {
         });
       }
 
-      return renderMarkdown(validated.markdown, {
-        ...(validated.language ? { language: validated.language } : {})
-      });
+      const rendered = renderMarkdownRequest(
+        validated.markdown,
+        validated.language
+      );
+      if (!rendered.success) {
+        return reply.code(400).send({
+          error: rendered.error,
+          message: rendered.message
+        });
+      }
+      return rendered.document;
     }
   );
 
@@ -304,10 +340,18 @@ export function buildApp(options: BuildAppOptions = {}) {
       }
 
       const markdownStartedAt = performance.now();
-      const rendered = renderMarkdown(validated.markdown, {
-        ...(validated.language ? { language: validated.language } : {})
-      });
+      const renderedResult = renderMarkdownRequest(
+        validated.markdown,
+        validated.language
+      );
       const markdownMs = performance.now() - markdownStartedAt;
+      if (!renderedResult.success) {
+        return reply.code(400).send({
+          error: renderedResult.error,
+          message: renderedResult.message
+        });
+      }
+      const rendered = renderedResult.document;
 
       try {
         const generated = await pdfGenerator.generate({