refactor: organize pages into folders

src/pages/PostRedirect/index.tsx

@@ -0,0 +1,41 @@
+import { useEffect } from "react";
+import { useNavigate, useParams } from "react-router-dom";
+import { getJSON } from "../../api";
+import { langQuery, useI18n } from "../../i18n";
+import { MOCK_POSTS } from "../../mocks/mockPosts";
+import { POST_STREAM_USES_MOCK } from "../../components/messageStream/hooks/usePostStream";
+import type { Post } from "../../types/post";
+
+export function PostRedirect() {
+  const { id } = useParams();
+  const { lang } = useI18n();
+  const navigate = useNavigate();
+
+  useEffect(() => {
+    if (!id) {
+      navigate("/browse", { replace: true });
+      return;
+    }
+
+    if (POST_STREAM_USES_MOCK) {
+      const post = MOCK_POSTS.find((p) => p.id === id);
+      navigate(
+        post ? `/category/${post.categorySlug}#post-${post.id}` : "/browse",
+        { replace: true },
+      );
+      return;
+    }
+
+    getJSON<Post>(
+      `/api/posts/${id}?lang=${encodeURIComponent(langQuery(lang))}`,
+    )
+      .then((post) => {
+        navigate(`/category/${post.categorySlug}#post-${post.id}`, {
+          replace: true,
+        });
+      })
+      .catch(() => navigate("/browse", { replace: true }));
+  }, [id, lang, navigate]);
+
+  return <div className="text-neutral-400">…</div>;
+}