Add JSDoc documentation and file headers to all source files

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/types/shims-vue.d.ts

@@ -1,6 +1,18 @@
-// src/types/shims-vue.d.ts
+// The Lucia project.
+// Copyright 2024-2026 DSP, inc.  All rights reserved.
+// Authors:
+//   cindy.chang@dsp.im (Cindy Chang), 2024/7/9
+//   imacat.yang@dsp.im (imacat), 2026/3/6
+/**
+ * @module types/shims-vue.d
+ *   Vue single-file component type shim for
+ *   TypeScript module resolution.
+ */
+
+/** Declares *.vue files as Vue components for TypeScript. */
 declare module '*.vue' {
     import { DefineComponent } from 'vue';
+    /** The default-exported Vue component. */
     const component: DefineComponent<{}, {}, any>;
     export default component;
   }