feat: add archives page with configurable menu (#386)

* feat: add archives page with configurable menu

* optimize: compat mobile layout

* fix: update archive menu layout

* fix: hide archives page from URL if showArchives is false

* docs: add `showArchives` option in docs

Resolves #361

---------

Co-authored-by: satnaing <satnaingdev@gmail.com>

src/utils/getPostsByGroupCondition.ts

@@ -0,0 +1,25 @@
+import type { CollectionEntry } from "astro:content";
+
+type GroupKey = string | number | symbol;
+
+interface GroupFunction<T> {
+  (item: T, index?: number): GroupKey;
+}
+
+const getPostsByGroupCondition = (
+  posts: CollectionEntry<"blog">[],
+  groupFunction: GroupFunction<CollectionEntry<"blog">>
+) => {
+  const result: Record<GroupKey, CollectionEntry<"blog">[]> = {};
+  for (let i = 0; i < posts.length; i++) {
+    const item = posts[i];
+    const groupKey = groupFunction(item, i);
+    if (!result[groupKey]) {
+      result[groupKey] = [];
+    }
+    result[groupKey].push(item);
+  }
+  return result;
+};
+
+export default getPostsByGroupCondition;