fix(nav): the address keeps what the app rewrites around it (review round 3)

- The Feed press over a live search ends only the search: the feed's own view stays named.
- Leaving a search steps back only off an entry the app pushed (_ytOwn); one a link or a reload
  opened is cleared in place, also where the Navigation API is missing.
- useUrlMirror rewrites a changed view through replaceView, so a reload's overlay marks go; its
  first write and its landing writes keep them for an overlay that reopens.
- Files and Playlists: a box emptied and filled again settles at once, never naming the ended search.
- Playlists: a linked player is scoped to the playlist the store started with, and only the rail's
  own move to the first playlist is no pick.
- Contract: writer objects are scanned to their matching brace, a computed or shorthand key is
  refused, and every useHistorySubview call hands a named definition.
- Lint: playwright/no-skipped-test also refuses fixme (gate snapshot regenerated).
- FEED_DEFAULT_SORT at the three remaining sites; linkedNotListed says to search by name.

frontend/src/moduleSearch.url.dom.test.tsx

@@ -20,13 +20,14 @@ import {
 } from "./features/navigation/navigationContext";
 import { ModuleStores } from "./features/navigation/ModuleStores";
 import { useChannels } from "./modules/channels/channelsContext";
-import { useFiles } from "./modules/files/filesContext";
-import { usePlaylists } from "./modules/playlists/playlistsContext";
+import { useFiles, useFilesActions } from "./modules/files/filesContext";
+import { usePlaylists, usePlaylistsActions } from "./modules/playlists/playlistsContext";
 import { usePlex } from "./modules/plex/plexContext";
 import { claimLocalData, getAccountRaw, LS, setAccountRaw } from "./lib/storage";
 
 const seen: { current: Record<string, string> } = { current: {} };
 const nav: { current: NavigationActions | null } = { current: null };
+const typeIn: { current: Record<string, (q: string) => void> } = { current: {} };
 
 function Probe() {
   const channels = useChannels();
@@ -34,8 +35,11 @@ function Probe() {
   const playlists = usePlaylists();
   const plex = usePlex();
   const actions = useNavigationActions();
+  const filesActions = useFilesActions();
+  const playlistsActions = usePlaylistsActions();
   useEffect(() => {
     nav.current = actions;
+    typeIn.current = { files: filesActions.setSearch, playlists: playlistsActions.setSearch };
     seen.current = {
       channels: channels.search,
       files: files.search,
@@ -115,5 +119,8 @@ describe.each([
     await waitFor(() => expect(seen.current[page]).toBe(""));
     // At once, not after the typing pause: a reload right after the return opens it unsearched.
     expect(search().get(key)).toBeNull();
+    // Typing again within the pause names the new text or nothing, never the ended search.
+    act(() => typeIn.current[page]!("x"));
+    expect(search().get(key)).not.toBe(value);
   });
 });