test(daemon): route the suite at its chokepoint and cover the protocol directly

Only 25 of the 83 CLI e2e tests actually reached a daemon: the helpers that
build a command bypassed the one place that routed. Routing at
TestServer::args instead brings that to 39 and, more importantly, puts the
streaming tests through a daemon — event.room and event.message delivery to a
remote client's mirror had no end-to-end coverage at all.

Adds what the command surface structurally cannot reach:

- Two clients against one daemon at once, which is the reason the hub exists
  and was proven nowhere in CI.
- tests/daemon_protocol_e2e.rs, speaking the socket by hand: TCP token
  required and socket token not, pre-auth refusal, error ids, notification
  silence, the line cap, the handshake timeout, and that a call shaped by the
  published contract is accepted.
- daemon status/stop/token as commands.
- A TUI unit test for conversation seeding, the part of the attach path that
  had actually been broken.

The protocol suite caught a regression in yesterday's hardening on its first
run: the socket was shut down before the writer flushed a failed handshake's
refusal, so a client with a wrong token saw the connection vanish instead of
being told why.

.github/workflows/ci.yml

@@ -108,6 +108,14 @@ jobs:
           SOULSEEK_E2E_REQUIRED: "1"
         run: cargo test -p soulseek-rs --test cli_e2e -- --nocapture
 
+      # The control protocol as a third party meets it: the TCP transport, the
+      # token, and the gate. None of it is reachable through the command
+      # surface, so the CLI suite cannot cover it in either mode.
+      - name: Run daemon protocol e2e tests (required against soulfind)
+        env:
+          SOULSEEK_E2E_REQUIRED: "1"
+        run: cargo test -p soulseek-rs --test daemon_protocol_e2e -- --nocapture --test-threads=1
+
       # The same suite again, with every session served by a daemon instead of
       # the command's own login. Identical records and exit codes both ways is
       # what makes daemon mode a routing decision rather than a second