give the soulseek workspace a url

The section is /soulseek/:section — nav entries are NavLinks, the view panel reads the same
URL instead of being told, and the dashboard's tiles and recent searches are real links (a
recent search now opens that search, not the search screen's front page).

The peer went in `?user=<name>` rather than the /soulseek/users/:name the audit sketched: a
second path segment would need a nested route just to keep the nav highlight, and `?search=`
had already set the convention there. That deletes the `soulseek:user` channel and with it a
`{username, nonce}` request the Users panel consumed-once and cleared — the nonce existed so
asking for the same peer twice counted twice. A link is idempotent, so there is nothing to
consume and nothing to disambiguate.

`soulseek:refresh` stays: it is a signal, which is what channels are for.

docs/navigation-audit.md

@@ -36,7 +36,7 @@ That fix is the template for the HIGH items below. **Caveat:** the fix only did
 ## Route map (from `App.tsx`)
 
 **Existing entity routes:** `/chat/:sessionId`, `/jobs/:id`, `/dashboards/:id`, `/projects/:id`, `/email/:emailId`.
-**Flat screens:** `/` `/files` `/music` `/soulseek` `/tasks` `/skills` `/processes` `/activity`
+**Flat screens:** `/` `/files` `/music` `/tasks` `/skills` `/processes` `/activity`
 `/system-monitor` `/task-logs` `/plans` `/terminal` `/desktop` `/browser` `/code-editor`.
 The five settings pages are route **pairs** now, not flat screens — `/settings/{profile,ai,system,integrations,user-management}`
 plus a `:section` each (M6). There has never been a `/settings/apps`; that entry was wrong when this list
@@ -87,12 +87,13 @@ is **one design decision** that cascades across many files:
 - **Music** — `Music/{MusicBrowser:182,209 · MusicDetail:138,174,234 · FavoritesView:85,107}` hold the entire
   library location in `usePanelChannel('music:cwd')`; every drill-in is `setCwd(path)`. No URL, no deep-link to
   an album. → back `music:cwd` with `/music?path=<rel>`; rows become `<Link>`s.
-- **Soulseek** — an entire workspace with **no URL at all**: `soulseek:section` nav (`SoulseekNav:40`,
-  `SoulseekDashboard:88/96/110/121`), `soulseek:user` peer channel (`UserMenu:32`, `SoulseekUsers:42`), and
-  per-panel `useState` for past-search (`SearchView:160`, a textbook `role="button"` div with `s.id` in the
-  closure), rooms (`SoulseekRooms:153`), conversations (`SoulseekChat:135`). → decide a nested tree
-  `/soulseek/:section` + `/soulseek/{users/:name, search/:id, rooms/:name, chat/:name}`. **S1 (the section nav)
-  decides S2–S7.**
+- ~~**Soulseek**~~ — **mostly done.** The section is `/soulseek/:section` (nav entries are `NavLink`s, the
+  view panel reads the same URL), the peer is `?user=<name>`, and the past-search was already `?search=<id>`.
+  The `soulseek:section` and `soulseek:user` channels are deleted; `soulseek:refresh` stays, which is a
+  signal and not selection. The peer went in the query string rather than `/soulseek/users/:name` as
+  sketched here, because the section nav has to stay a one-segment `NavLink` — a second path segment would
+  need a nested route just to keep the highlight, and the query string is what `?search=` already uses.
+  Still on `useState`: rooms (`SoulseekRooms`) and conversations (`SoulseekChat`).
 
 ### 🟡 LOW / borderline
 
@@ -120,8 +121,6 @@ This is the primary surface to convert to URL-driven selection.
 | `SELECTED_PROJECT` (`useGlobal`) | selected project | `/projects/:id` | `ProjectListApp.tsx:45`, `ProjectPreview.tsx:386` (H3) |
 | `EMAIL_SELECTED` | open email | `/email/:emailId` | `EmailList.tsx:336`, `EmailScreen.tsx` sync (H5) |
 | `music:cwd` | library location (album/artist/folder) | `/music?path=` | `MusicBrowser/MusicDetail/FavoritesView` |
-| `soulseek:section` | active Soulseek section | `/soulseek/:section` | `SoulseekNav/View/Dashboard/UserMenu` |
-| `soulseek:user` | selected peer | `/soulseek/users/:name` | `UserMenu.tsx:28`, `SoulseekUsers.tsx:34` |
 | local `useState` selections | search / room / conversation / peer / open file / preview slug | respective nested routes | `SearchView`, `SoulseekRooms`, `SoulseekChat`, `SoulseekUsers`, `CodeEditor/useEditorState`, `PreviewProvider` |
 
 **Excluded — event-bus / refresh signals, NOT selection:** `files:refresh-signal`,
@@ -201,7 +200,7 @@ publishers means changing the chat panel, which is another agent's, so it is wri
 
 ### Phase 3 — Whole-workspace routing decisions (needs a design call first)
 - [ ] **Music** — decide `/music?path=` (or nested); back `music:cwd` with the URL; rows → `<Link>` (M-music).
-- [ ] **Soulseek** — decide the nested tree `/soulseek/:section` + `/soulseek/{users,search,rooms,chat}/:x`; **S1 decides S2–S7** (M-slsk).
+- [x] **Soulseek** — `/soulseek/:section` with the peer in `?user=` and the search already in `?search=`; the two selection channels are deleted. Rooms and conversations are still `useState`. **Needs runtime test.**
 - [x] **M10** SystemMonitor scope → `/system-monitor/:scope`; `monitor:scope` channel deleted. **Needs runtime test.**
 - [ ] **M9** Plans → `/plans/:name` (`Plans/index.tsx:36`).