fix(nav): a linked player, file and search survive what the app does by itself (review round 2)

- Playlists: a link over a playlist the account does not hold plays alone; the rail's own
  fallback no longer counts as a pick that gives the player up.
- The linked opener opens or clears nothing once the address names another player, and stops
  looking (and fetching its row) once it settled.
- Files: a list the server's cap cut — the sorted or searched one too — keeps the link, with a
  notice of its own (EN/HU).
- History: an in-place view rewrite (search refine, count, channel to channel, sub-view)
  drops a reloaded entry's overlay marks (replaceView); a landing on a channel opened from a
  search keeps the search; the Feed press on a search opens the plain feed.
- Files/Playlists: an emptied search is written at once.
- Client log: plf/cf (column text filters) are typed keys; the shell has none of its own.
- Contract: writers outside lib/ take a literal or a lib/ function's result; every URL key is
  sorted typed or not; the writer regexes are held by a fixture; sub-views named; the bookmark
  net reads page tags.
- Feed defaults in one constant; one live-search queue helper; Scheduler writes through the
  Activity codec; notRun copy (EN/HU) names Forward and a plain "Search YouTube" button.

frontend/src/lib/moduleDef.ts

@@ -50,9 +50,9 @@ export type ModuleDef = {
   // along onto another's URL. Empty for a page with nothing of its own in the URL. Each key belongs to
   // one module and none is a shell key (moduleUrl.contract.test).
   urlKeys: readonly string[];
-  // Those of them that carry what the user TYPED (a search box's text): the client log keeps their
-  // values out below its most detailed level, as it does the shell's own (lib/logHooks). A new search
-  // box's key is declared here with it (moduleUrl.contract.test holds them to urlKeys).
+  // Those of them that carry what the user TYPED (a search box's text, a column filter map holding a
+  // text filter): the client log keeps their values out below its most detailed level (lib/logHooks).
+  // moduleUrl.contract.test sorts every key of urlKeys as typed or not, so a new one is decided.
   typedUrlKeys?: readonly string[];
   // Its page plays YouTube videos in the player and reopens it from an address that names one (a
   // reload, a bookmark — lib/playerUrlState), with its own list as the queue. A page without it gets