Hide unsubscribed channels from the channels list, add a Saved tab

- GET /api/channels called with subscribed=true from the Channels page, so
  a channel disappears from the list as soon as it's unsubscribed instead
  of lingering with a badge
- GET /api/feed gains a `downloaded` filter (this was already anticipated
  in the original TZ's feed query params but left unimplemented until
  download_jobs existed) -- matches on each video's *latest* job only, so
  a redownload/delete history doesn't leave stale matches
- New /saved route: same category filtering, video grid and download
  actions as the main feed, scoped to downloaded videos only

2 new backend tests (76 total).
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

frontend/src/App.tsx

@@ -3,6 +3,7 @@ import { Route, Routes } from 'react-router-dom'
 import { getAuthStatus } from './api/client'
 import Connect from './pages/Connect'
 import Feed from './pages/Feed'
+import Saved from './pages/Saved'
 import Channels from './pages/Channels'
 import ChannelVideos from './pages/ChannelVideos'
 import VideoPage from './pages/VideoPage'
@@ -43,6 +44,7 @@ function App() {
     <div className="app">
       <Routes>
         <Route path="/" element={<Feed />} />
+        <Route path="/saved" element={<Saved />} />
         <Route path="/channels" element={<Channels />} />
         <Route path="/channels/:channelId/videos" element={<ChannelVideos />} />
         <Route path="/video/:youtubeVideoId" element={<VideoPage />} />

frontend/src/api/client.ts

@@ -64,12 +64,13 @@ export function getChannel(channelId: number) {
 }
 
 export function listChannels(
-  params: { search?: string; categoryId?: number; uncategorized?: boolean } = {},
+  params: { search?: string; categoryId?: number; uncategorized?: boolean; subscribed?: boolean } = {},
 ) {
   const qs = new URLSearchParams()
   if (params.search) qs.set('search', params.search)
   if (params.categoryId != null) qs.set('category_id', String(params.categoryId))
   if (params.uncategorized) qs.set('uncategorized', 'true')
+  if (params.subscribed != null) qs.set('subscribed', String(params.subscribed))
   const suffix = qs.toString() ? `?${qs.toString()}` : ''
   return request<ChannelDto[]>(`/api/channels${suffix}`)
 }
@@ -199,12 +200,19 @@ export function recheckLocal(youtubeVideoId: string) {
 }
 
 export function getFeed(
-  params: { categoryId?: number; uncategorized?: boolean; channelId?: number; cursor?: string } = {},
+  params: {
+    categoryId?: number
+    uncategorized?: boolean
+    channelId?: number
+    downloaded?: boolean
+    cursor?: string
+  } = {},
 ) {
   const qs = new URLSearchParams()
   if (params.categoryId != null) qs.set('category_id', String(params.categoryId))
   if (params.uncategorized) qs.set('uncategorized', 'true')
   if (params.channelId != null) qs.set('channel_id', String(params.channelId))
+  if (params.downloaded) qs.set('downloaded', 'true')
   if (params.cursor) qs.set('cursor', params.cursor)
   const suffix = qs.toString() ? `?${qs.toString()}` : ''
   return request<{ items: FeedVideoDto[]; next_cursor: string | null }>(`/api/feed${suffix}`)

frontend/src/pages/Channels.tsx

@@ -16,6 +16,7 @@ function Channels() {
     queryKey: ['channels', filter],
     queryFn: () =>
       listChannels({
+        subscribed: true,
         categoryId: typeof filter === 'number' ? filter : undefined,
         uncategorized: filter === 'uncategorized',
       }),
@@ -58,6 +59,7 @@ function Channels() {
         <h1>Каналы</h1>
         <div className="actions">
           <Link to="/">Лента</Link>
+          <Link to="/saved">Сохранённые</Link>
           <Link to="/categories">Категории</Link>
           <button onClick={() => syncMutation.mutate()} disabled={running}>
             {running ? 'Синхронизация...' : 'Обновить сейчас'}

frontend/src/pages/Feed.tsx

@@ -53,6 +53,7 @@ function Feed() {
       <header>
         <h1>Лента</h1>
         <div className="actions">
+          <Link to="/saved">Сохранённые</Link>
           <Link to="/channels">Каналы</Link>
           <Link to="/categories">Категории</Link>
           <button onClick={() => syncMutation.mutate()} disabled={running}>

frontend/src/pages/Saved.tsx

@@ -0,0 +1,70 @@
+import { useInfiniteQuery, useQuery } from '@tanstack/react-query'
+import { Link } from 'react-router-dom'
+import { getFeed, listCategories } from '../api/client'
+import CategoryNav, { type CategoryFilter } from '../components/CategoryNav'
+import VideoCard from '../components/VideoCard'
+import { useState } from 'react'
+
+function Saved() {
+  const [filter, setFilter] = useState<CategoryFilter>('all')
+
+  const categoriesQuery = useQuery({ queryKey: ['categories'], queryFn: listCategories })
+  const categories = categoriesQuery.data ?? []
+
+  const feedQuery = useInfiniteQuery({
+    queryKey: ['feed', 'saved', filter],
+    queryFn: ({ pageParam }) =>
+      getFeed({
+        categoryId: typeof filter === 'number' ? filter : undefined,
+        uncategorized: filter === 'uncategorized',
+        downloaded: true,
+        cursor: pageParam,
+      }),
+    initialPageParam: undefined as string | undefined,
+    getNextPageParam: (lastPage) => lastPage.next_cursor ?? undefined,
+  })
+
+  const items = feedQuery.data?.pages.flatMap((page) => page.items) ?? []
+
+  return (
+    <div className="feed-screen">
+      <header>
+        <h1>Сохранённые</h1>
+        <div className="actions">
+          <Link to="/">Лента</Link>
+          <Link to="/channels">Каналы</Link>
+          <Link to="/categories">Категории</Link>
+        </div>
+      </header>
+
+      <div className="layout">
+        <CategoryNav categories={categories} value={filter} onChange={setFilter} />
+
+        <div className="content">
+          {feedQuery.isLoading && <p>Загрузка...</p>}
+          {feedQuery.isError && <p className="error">Не удалось загрузить сохранённые видео</p>}
+
+          <ul className="video-grid">
+            {items.map((video) => (
+              <VideoCard key={video.youtube_video_id} video={video} />
+            ))}
+          </ul>
+
+          {!feedQuery.isLoading && items.length === 0 && <p>Здесь пока пусто. Скачай видео из ленты.</p>}
+
+          {feedQuery.hasNextPage && (
+            <button
+              className="load-more"
+              onClick={() => feedQuery.fetchNextPage()}
+              disabled={feedQuery.isFetchingNextPage}
+            >
+              {feedQuery.isFetchingNextPage ? 'Загрузка...' : 'Показать ещё'}
+            </button>
+          )}
+        </div>
+      </div>
+    </div>
+  )
+}
+
+export default Saved