improvement(channel): bring the actions to the tabs, list every channel

Channel page: the actions sat in the header's top-right corner, a page-width
mouse trip from anything else you'd click. There are only ever two tabs, so
they ride the tab row now, right next to About.

Channel picker: drop the 50-row cap — 320 plain buttons cost nothing to render
(the feed virtualises thousands), so the whole list scrolls in the same box. The
cap was caution, not a measurement. The box gets the app's usual edge-fade to
hint at more, and a line saying "Priority first, then A-Z" — the backend orders
by `priority DESC, lower(title)`, which reads as random to anyone who hasn't set
a priority.

frontend/src/components/ChannelPage.tsx

@@ -284,7 +284,26 @@ export default function ChannelPage({
               ))}
             </div>
           </div>
-          <div className="flex items-center gap-2 shrink-0 pb-1">
+        </div>
+
+        {exploring && (
+          <div className="flex items-center gap-2 text-xs text-muted mt-2">
+            <Loader2 className="w-3.5 h-3.5 animate-spin" />
+            {t("channel.loadingVideos")}
+          </div>
+        )}
+
+        {/* Tabs — the channel actions ride along here rather than off in the header's top-right
+            corner: there are only ever two tabs, so there's room, and it keeps the things you click
+            within a few pixels of each other instead of across the page. */}
+        <div className="flex items-center gap-4 mt-3 border-b border-border">
+          <button onClick={() => setTab("videos")} className={tabClass(tab === "videos")}>
+            {t("channel.tabVideos")}
+          </button>
+          <button onClick={() => setTab("about")} className={tabClass(tab === "about")}>
+            {t("channel.tabAbout")}
+          </button>
+          <div className="ml-2 flex items-center gap-2 pb-1.5">
             <a
               href={ytUrl}
               target="_blank"
@@ -344,23 +363,6 @@ export default function ChannelPage({
               ))}
           </div>
         </div>
-
-        {exploring && (
-          <div className="flex items-center gap-2 text-xs text-muted mt-2">
-            <Loader2 className="w-3.5 h-3.5 animate-spin" />
-            {t("channel.loadingVideos")}
-          </div>
-        )}
-
-        {/* Tabs */}
-        <div className="flex items-center gap-4 mt-3 border-b border-border">
-          <button onClick={() => setTab("videos")} className={tabClass(tab === "videos")}>
-            {t("channel.tabVideos")}
-          </button>
-          <button onClick={() => setTab("about")} className={tabClass(tab === "about")}>
-            {t("channel.tabAbout")}
-          </button>
-        </div>
       </div>
 
       {/* Tab content */}

frontend/src/components/ChannelPicker.tsx

@@ -3,10 +3,9 @@ import { useTranslation } from "react-i18next";
 import { useQuery } from "@tanstack/react-query";
 import { X } from "lucide-react";
 import { api, type FeedFilters } from "../lib/api";
+import { useScrollFade } from "../lib/useScrollFade";
 import { inputCls } from "./ui/form";
 
-const MAX_ROWS = 50;
-
 // Pick one channel to narrow the feed to. Until this existed, `filters.channelId` was settable only
 // via a shared "?channel=" link — the panel had a remove button for a filter nothing could apply.
 //
@@ -22,6 +21,8 @@ export default function ChannelPicker({
 }) {
   const { t } = useTranslation();
   const [query, setQuery] = useState("");
+  // Same edge-fade affordance the nav rail and the panel body use to hint at more content.
+  const fade = useScrollFade();
   const channelsQuery = useQuery({
     queryKey: ["channels"],
     queryFn: api.channels,
@@ -47,7 +48,6 @@ export default function ChannelPicker({
   const q = query.trim().toLowerCase();
   const all = channelsQuery.data ?? [];
   const matches = q ? all.filter((c) => (c.title ?? c.id).toLowerCase().includes(q)) : all;
-  const shown = matches.slice(0, MAX_ROWS);
 
   return (
     <>
@@ -58,18 +58,28 @@ export default function ChannelPicker({
         aria-label={t("sidebar.channelSearch")}
         className={inputCls}
       />
-      <div className="mt-1.5 max-h-44 overflow-y-auto no-scrollbar flex flex-col gap-0.5">
+      {/* The order isn't arbitrary and isn't alphabetical — say so, or the top of the list looks
-        {shown.length === 0 ? (
+          random to anyone who hasn't set a priority. Only while unfiltered: a search reorders nothing
+          but does drop the rows that explain it. */}
+      {!q && all.length > 0 && (
+        <div className="px-2 pt-1.5 text-[11px] text-muted">{t("sidebar.channelOrder")}</div>
+      )}
+      <div
+        ref={fade.ref}
+        style={fade.style}
+        className="mt-1.5 max-h-44 overflow-y-auto no-scrollbar flex flex-col gap-0.5"
+      >
+        {matches.length === 0 ? (
           <div className="px-2 py-1.5 text-xs text-muted">
             {channelsQuery.isLoading ? t("sidebar.loading") : t("sidebar.noChannelMatch")}
           </div>
         ) : (
-          shown.map((c) => (
+          matches.map((c) => (
             <button
               key={c.id}
               onClick={() => setFilters({ ...filters, channelId: c.id, channelName: c.title ?? undefined })}
-              // shrink-0 is load-bearing: these are flex children in a max-height box, so without it
+              // shrink-0 is load-bearing: these are flex children in a max-height box, so without them
-              // fifty of them squash to ~12px each and clip their own text instead of scrolling.
+              // they squash to ~12px each and clip their own text instead of the box scrolling.
               className="w-full shrink-0 text-left text-sm px-2 py-1.5 rounded-lg text-muted hover:text-fg hover:bg-card truncate transition"
             >
               {c.title ?? c.id}
@@ -77,13 +87,6 @@ export default function ChannelPicker({
           ))
         )}
       </div>
-      {/* The list is a picker, not a browser — but say so when it's cut off, rather than just
-          stopping and letting a channel look absent. */}
-      {matches.length > shown.length && (
-        <div className="px-2 pt-1.5 text-[11px] text-muted">
-          {t("sidebar.channelMore", { shown: shown.length, total: matches.length })}
-        </div>
-      )}
     </>
   );
 }

frontend/src/i18n/locales/en/sidebar.json

@@ -76,5 +76,5 @@
   },
   "channelSearch": "Search channels…",
   "noChannelMatch": "No channel matches.",
-  "channelMore": "Showing {{shown}} of {{total}} — search to narrow."
+  "channelOrder": "Priority first, then A–Z"
 }

frontend/src/i18n/locales/hu/sidebar.json

@@ -76,5 +76,5 @@
   },
   "channelSearch": "Csatornák keresése…",
   "noChannelMatch": "Nincs találat.",
-  "channelMore": "{{total}} közül {{shown}} látszik — keress a szűkítéshez."
+  "channelOrder": "Prioritás szerint, majd A–Z"
 }