soulseek, extracted into plugins/soulseek — the platform half

Seventh extraction, and the first of something that was already dead. Soulseek
had been switched off since 2026-08-13: hono.ts carried the router import and
its PROTECTED_MOUNTS entry commented out, so createSidecarProxy never ran and
registerProxiedPrefix was never called; officer-slskd was not in the ecosystem
at all. Because the permission entry had been reduced to api: [], the totality
check was satisfied and the server booted clean — the UI rendered and every
request 404'd. Worth naming: the boot check proves every MOUNTED prefix has a
permission, and is silent about a feature that mounts nothing.

Also closes a live data hazard: schema.ts had the soulseek export commented
out, so the three tables were absent from the drizzle barrel and bun db:push
would have dropped soulseek_favorites, soulseek_browse_snapshots and
soulseek_browse_dirs on any server holding them. rebuild-soulseek-tree.ts
documented the workaround rather than the problem; deleted with the rest.

The connection stays in core service_connections under service 'slskd' while
the mount is now /api/soulseek. Those differ on purpose.

Test fixtures: slskd was canonical in three app-store tests, the third
extraction running to break them. installer.test.ts now builds a literal
fixture instead of reaching into the catalogue — it pins planSteps, which is
installer logic, and no catalogue entry is both provisioned and members:'none'
any more. catalogue.test.ts and members.test.ts re-anchored to vnc/notify/gitea.

Unrelated but mine: check:theme caught 5 palette classes I introduced in
CommandHQ earlier tonight against a baseline of 0. Converted to bg-success /
bg-warning. check:theme is not part of bun test, which is why the green suite
never showed it.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

scripts/theme-baseline.json

@@ -1,5 +1,5 @@
 {
-  "src/apps/officer-web/Screens": 144,
+  "src/apps/officer-web/Screens": 122,
   "src/workspaces/components": 47,
   "src/workspaces/officerdev/src/apps/AppStore": 6,
   "src/workspaces/officerdev/src/apps/Chat": 12,
@@ -11,13 +11,9 @@
   "src/workspaces/officerdev/src/apps/FileViewer": 38,
   "src/workspaces/officerdev/src/apps/Invoices": 95,
   "src/workspaces/officerdev/src/apps/Jellyfin": 48,
-  "src/workspaces/officerdev/src/apps/Photos": 47,
   "src/workspaces/officerdev/src/apps/Preview": 4,
   "src/workspaces/officerdev/src/apps/QrTransfer": 5,
-  "src/workspaces/officerdev/src/apps/Soulseek": 313,
   "src/workspaces/officerdev/src/apps/SystemMonitor": 1,
   "src/workspaces/officerdev/src/apps/Terminal": 10,
-  "src/workspaces/officerdev/src/apps/Transmission": 43,
-  "src/workspaces/officerdev/src/apps/Wallet": 68,
-  "src/workspaces/officerdev/src/components": 22
+  "src/workspaces/officerdev/src/apps/Wallet": 68
 }