fix: Add basePath to API reference links

Apply BASE_PATH prefix to API package links in sidebar
and index page for GitHub Pages compatibility.

Author: lambdalisue

templates/api/ApiPage.tsx

@@ -74,7 +74,11 @@ function PackageGroupSection({ group }: PackageGroupSectionProps) {
       </h2>
       <div class="package-grid">
         {group.packages.map((pkg) => (
-          <a key={pkg.name} href={`/api/${pkg.name}`} class="package-card">
+          <a
+            key={pkg.name}
+            href={`${basePath}/api/${pkg.name}/`}
+            class="package-card"
+          >
             <h3>{pkg.specifier}</h3>
             <div class="package-meta">
               <span class="package-version">v{pkg.version}</span>

templates/api/components.tsx

@@ -37,6 +37,7 @@ import {
   extractTypeParamRefs,
   extractTypeRefs,
 } from "../../lib/type-references.ts";
+import { basePath } from "../../data/docs.ts";
 
 // ============================================================================
 // Type Display Components (with linking)
@@ -232,7 +233,7 @@ function renderTypeName(name: string, ctx: TypeLinkContext): Child {
     if (targetPackage !== currentPackage) {
       return (
         <a
-          href={`/api/${targetPackage}#${name}`}
+          href={`${basePath}/api/${targetPackage}/#${name}`}
           class="type-link type-link-cross-package"
         >
           {name}
@@ -1225,7 +1226,7 @@ export function PackageSidebar(
                   key={pkg.name}
                   class={pkg.name === currentPackage ? "active" : ""}
                 >
-                  <a href={`/api/${pkg.name}`}>{pkg.name}</a>
+                  <a href={`${basePath}/api/${pkg.name}/`}>{pkg.name}</a>
                 </li>
               ))}
             </ul>