release: 发布 v0.5.0

新增共享 Preview Engine，统一 Web 连续预览、快速分页、Playwright PDF 与 Electron PDF；实现稳定前缀复用和修改位置后的增量分页，保留媒体块按文档顺序串行回填与单次重排。

完善跨端链接与桌面文档工作流：Web 受控处理锚点和 HTTP/HTTPS 外链；Desktop 支持本地路径、file URI、系统协议、多窗口、同文件单例、Markdown 当前或新窗口打开，以及聚焦时外部文件变化提示。

统一四套内置主题名称并默认使用 Typora Github；修复连续预览双滚动条、ECharts 尺寸、PDF 本地链接、围栏代码块 Typora DOM 与重复行内样式；桌面发行链强制完整重建内嵌 Web，避免安装包携带陈旧资源。

发布 Web/Compose 与 Windows NSIS/ZIP：镜像 yixiong/md-to-pdf:v0.5.0 已健康部署；NSIS SHA-256 为 60992D1FDCA513F46346C78478537EB4159D8C0E76B41ECF3CDC25BE77707D92，ZIP SHA-256 为 D74F82293FB67126E583546CBA894569EFC9A0B1B6343FAC648CCC95F1D188D8，本机安装版已升级至 v0.5.0。

验证：全项目 238 项测试通过，类型检查、生产构建和 git diff --check 通过；Web 快速/连续/精确预览、Compose、Desktop 多窗口、窗口状态、文件关联、链接与代码块均完成真实环境验收。

packages/core/src/document-link.ts

@@ -0,0 +1,123 @@
+export type DocumentLinkKind =
+  | "anchor"
+  | "network"
+  | "protocol"
+  | "local"
+  | "unsafe"
+  | "invalid";
+
+export interface ClassifiedDocumentLink {
+  kind: DocumentLinkKind;
+  href: string;
+  normalizedHref: string;
+  scheme?: string;
+}
+
+const schemePattern = /^([a-z][a-z\d+.-]*):/iu;
+const windowsAbsolutePathPattern = /^[a-z]:[\\/]/iu;
+const windowsUncPathPattern = /^\\\\[^\\]/u;
+const unsafeSchemePattern = /^(?:data|javascript|vbscript)$/u;
+const controlCharacterPattern = /[\u0000-\u001f\u007f]/u;
+const pdfLocalLinkOrigin = "https://mdpdf.local.invalid";
+const pdfLocalLinkPath = "/document-link";
+
+function result(
+  kind: DocumentLinkKind,
+  href: string,
+  normalizedHref = href,
+  scheme?: string
+): ClassifiedDocumentLink {
+  return {
+    kind,
+    href,
+    normalizedHref,
+    ...(scheme ? { scheme } : {})
+  };
+}
+
+export function classifyDocumentLink(
+  rawHref: string
+): ClassifiedDocumentLink {
+  const href = rawHref.trim();
+  if (!href || controlCharacterPattern.test(href)) {
+    return result("invalid", href);
+  }
+
+  if (href.startsWith("#")) {
+    return result("anchor", href);
+  }
+
+  if (
+    windowsAbsolutePathPattern.test(href) ||
+    windowsUncPathPattern.test(href)
+  ) {
+    return result("local", href);
+  }
+
+  if (href.startsWith("//")) {
+    return result("network", href, `https:${href}`, "https");
+  }
+
+  const schemeMatch = schemePattern.exec(href);
+  if (!schemeMatch) {
+    return result("local", href);
+  }
+
+  const scheme = schemeMatch[1]?.toLowerCase() ?? "";
+  if (unsafeSchemePattern.test(scheme)) {
+    return result("unsafe", href, href, scheme);
+  }
+
+  if (scheme === "http" || scheme === "https") {
+    try {
+      const url = new URL(href);
+      if (!url.hostname) {
+        return result("invalid", href, href, scheme);
+      }
+      return result("network", href, href, scheme);
+    } catch {
+      return result("invalid", href, href, scheme);
+    }
+  }
+
+  if (scheme === "file") {
+    return result("local", href, href, scheme);
+  }
+
+  return result("protocol", href, href, scheme);
+}
+
+export function isSafeDocumentLink(rawHref: string) {
+  const { kind } = classifyDocumentLink(rawHref);
+  return kind !== "unsafe" && kind !== "invalid";
+}
+
+export function encodeLocalDocumentLinkForPdf(rawHref: string) {
+  const link = classifyDocumentLink(rawHref);
+  if (link.kind !== "local") {
+    return undefined;
+  }
+  const encoded = new URL(pdfLocalLinkPath, pdfLocalLinkOrigin);
+  encoded.searchParams.set("href", link.href);
+  return encoded.href;
+}
+
+export function decodeLocalDocumentLinkFromPdf(rawHref: string) {
+  let encoded: URL;
+  try {
+    encoded = new URL(rawHref);
+  } catch {
+    return undefined;
+  }
+  if (
+    encoded.origin !== pdfLocalLinkOrigin ||
+    encoded.pathname !== pdfLocalLinkPath
+  ) {
+    return undefined;
+  }
+  const href = encoded.searchParams.get("href");
+  if (!href || classifyDocumentLink(href).kind !== "local") {
+    return undefined;
+  }
+  return href;
+}

packages/core/src/index.ts

@@ -1,3 +1,4 @@
 export * from "./document.js";
+export * from "./document-link.js";
 export * from "./export-config.js";
 export * from "./theme.js";