chore: remove frontend files

frontend/src/App.tsx

@@ -1,14 +0,0 @@
-import React from "react";
-import FeedList from "../components/FeedList";
-import EpisodeList from "../components/EpisodeList";
-
-export default function App() {
-  return (
-    <div style={{ padding: "20px", fontFamily: "sans-serif" }}>
-      <h1>ポッドキャスト自動生成サービス 管理画面</h1>
-      <FeedList />
-      <hr style={{ margin: "20px 0" }} />
-      <EpisodeList />
-    </div>
-  );
-}

frontend/src/app/page.tsx

@@ -1,14 +0,0 @@
-import React from "react";
-import FeedList from "../components/FeedList";
-import EpisodeList from "../components/EpisodeList";
-
-export default function Home() {
-  return (
-    <div style={{ padding: "20px", fontFamily: "sans-serif" }}>
-      <h1>ポッドキャスト自動生成サービス 管理画面</h1>
-      <FeedList />
-      <hr style={{ margin: "20px 0" }} />
-      <EpisodeList />
-    </div>
-  );
-}

frontend/src/components/EpisodeList.tsx

@@ -1,61 +0,0 @@
-import React, { useEffect, useState } from "react";
-
-interface Episode {
-  id: string;
-  title: string;
-  pubDate: string;
-  audioPath: string;
-  sourceLink: string;
-}
-
-export default function EpisodeList() {
-  const [episodes, setEpisodes] = useState<Episode[]>([]);
-
-  useEffect(() => {
-    fetch("/api/episodes")
-      .then((res) => res.json())
-      .then((data) => setEpisodes(data));
-  }, []);
-
-  return (
-    <div>
-      <h2>エピソード一覧</h2>
-      <table style={{ width: "100%", borderCollapse: "collapse" }}>
-        <thead>
-          <tr>
-            <th style={{ border: "1px solid #ccc", padding: "8px" }}>
-              タイトル
-            </th>
-            <th style={{ border: "1px solid #ccc", padding: "8px" }}>
-              公開日時
-            </th>
-            <th style={{ border: "1px solid #ccc", padding: "8px" }}>
-              プレビュー
-            </th>
-          </tr>
-        </thead>
-        <tbody>
-          {episodes.map((ep) => (
-            <tr key={ep.id}>
-              <td style={{ border: "1px solid #ccc", padding: "8px" }}>
-                {ep.title}
-              </td>
-              <td style={{ border: "1px solid #ccc", padding: "8px" }}>
-                {new Date(ep.pubDate).toLocaleString("ja-JP")}
-              </td>
-              <td style={{ border: "1px solid #ccc", padding: "8px" }}>
-                <audio controls preload="none">
-                  <source
-                    src={`/podcast_audio/${ep.id}.mp3`}
-                    type="audio/mpeg"
-                  />
-                  お使いのブラウザは audio タグに対応していません。
-                </audio>
-              </td>
-            </tr>
-          ))}
-        </tbody>
-      </table>
-    </div>
-  );
-}

frontend/src/components/FeedList.tsx

@@ -1,45 +0,0 @@
-import React, { useEffect, useState } from "react";
-
-export default function FeedList() {
-  const [feeds, setFeeds] = useState<string[]>([]);
-  const [newUrl, setNewUrl] = useState("");
-
-  useEffect(() => {
-    fetch("/api/feeds")
-      .then((res) => res.json())
-      .then((data) => setFeeds(data));
-  }, []);
-
-  const addFeed = async () => {
-    if (!newUrl) return;
-    await fetch("/api/feeds", {
-      method: "POST",
-      headers: { "Content-Type": "application/json" },
-      body: JSON.stringify({ feedUrl: newUrl }),
-    });
-    setNewUrl("");
-    const updated = await fetch("/api/feeds").then((res) => res.json());
-    setFeeds(updated);
-  };
-
-  return (
-    <div>
-      <h2>RSSフィード管理</h2>
-      <ul>
-        {feeds.map((url) => (
-          <li key={url}>{url}</li>
-        ))}
-      </ul>
-      <input
-        type="text"
-        placeholder="RSSフィードURLを入力"
-        value={newUrl}
-        onChange={(e) => setNewUrl(e.target.value)}
-        style={{ width: "300px" }}
-      />
-      <button onClick={addFeed} style={{ marginLeft: "8px" }}>
-        追加
-      </button>
-    </div>
-  );
-}

frontend/src/index.tsx

@@ -1 +0,0 @@
-// This file can be removed since Next.js handles the entry point automatically