fix(nav): the address follows the view through overlays, reloads and Back (review round 1)

- A URL mirror names the view again on every entry Back or Forward lands on, so a change made
  under a dialog, a drawer or a sub-view is not undone by the next reload.
- A view pushed from the entry a reload under a dialog started from no longer inherits its overlay
  mark; a reload under two overlays closes onto the page in one step.
- The linked player reopens over a live search, gives itself up when its list moves first, and
  plays alone over an emptied playlist; a capped Files list keeps the link it cannot resolve.
- The Feed press over a channel ends the search; leaving a search ends its asked mark; Files and
  Playlists searches end with their page; the feed always names its view and debounces its search.
- Search-box keys are declared per module and kept out of the client log below TRACE.
- Writers outside lib/ go through codecs; the URL contract scans computed keys, overlay writers and
  two-line reads, and holds every page to a bookmark round trip (Config, Activity, Playlists and the
  Files sort and viewer added).

docs/development.md

@@ -49,11 +49,13 @@ A frontend page is one folder, `frontend/src/modules/<id>/` (the layering is in
    address-bar key its view writes (the URL is the view: a bookmark reopens it), its list kept in `lib/` beside
    its codec; the shell clears them on a page switch and opens a page without another page's keys.
    Every setting the page shows — a tab, a sort, a filter, a search, the item open in it — goes there: a codec
-   in `lib/<id>UrlState.ts` (read the params into the view, write the view as updates, a default left out),
-   written with `useUrlMirror` (a sub-view through `useHistorySubview`'s `url`, an overlay through
-   `useBackToClose`'s), read back first on mount (a link wins over anything remembered). Add its round trip to
-   `e2e/bookmark.spec.ts`. Only what an address cannot promise to reopen stays out, said in its codec (Home's
-   draw, `lib/homeUrlState`).
+   in `lib/<id>UrlState.ts` (read the params into the view, write the view as updates, a default left out —
+   or always written, when an address naming none falls back to a view remembered elsewhere), written with
+   `useUrlMirror` (a sub-view through `useHistorySubview`'s `url`, an overlay through `useBackToClose`'s),
+   always as the codec's result: a writer outside `lib/` computes no key of its own. Read back first on mount
+   (a link wins over anything remembered). A search box's key is also in `typedUrlKeys` (the client log keeps
+   what was typed out). Add its round trip to `e2e/bookmark.spec.ts`. Only what an address cannot promise to
+   reopen stays out, said in its codec (Home's draw, `lib/homeUrlState`).
 3. `index.ts`, the module's public face: the definition, and only what other folders must read (its store's
    hooks). Another folder reaches the module through this file or not at all.
 4. The id in `lib/urlState`'s `PAGES`, and the definition in `features/navigation/moduleRegistry.ts`, in
@@ -67,7 +69,8 @@ A frontend page is one folder, `frontend/src/modules/<id>/` (the layering is in
 
 What holds it: `moduleRegistry.contract.test.ts` (every id defined once, from its own folder, lazily),
 `moduleStores.contract.test.tsx` (no store reads another module), `moduleUrl.contract.test.ts` (each URL key
-belongs to one module and matches what its codec writes; no undeclared key literal), the `local/layers` lint rule (imports only go
+belongs to one module and matches what its codec writes; a writer outside `lib/` computes no key; no key literal
+written or read from the live query undeclared; every page with keys in the bookmark net), the `local/layers` lint rule (imports only go
 down, a module only through its face) and `chunkGuard` in the build (no lazy page on the boot path), plus the
 i18n parity test.