feat(irc): add interactive setup

feat(gateway): refine Platform._missing_ and platform-connected dispatch

Restricts plugin-name acceptance to bundled plugin scan + registry
(no arbitrary string -> enum-pollution), pulls per-platform connectivity
checks into a _PLATFORM_CONNECTED_CHECKERS lambda map with a clean
_is_platform_connected method, and adds tests covering the checker map,
plugin platform interface, and IRC setup wizard.

tests/hermes_cli/test_doctor.py

@@ -430,6 +430,43 @@ def test_run_doctor_accepts_hermes_provider_ids_that_catalog_aliases(
         )
 
 
+def test_run_doctor_accepts_bare_custom_provider(monkeypatch, tmp_path):
+    home = tmp_path / ".hermes"
+    home.mkdir(parents=True, exist_ok=True)
+    (home / "config.yaml").write_text(
+        "model:\n"
+        "  provider: custom\n"
+        "  default: local-model\n"
+        "  base_url: http://localhost:8000/v1\n",
+        encoding="utf-8",
+    )
+
+    monkeypatch.setattr(doctor_mod, "HERMES_HOME", home)
+    monkeypatch.setattr(doctor_mod, "PROJECT_ROOT", tmp_path / "project")
+    monkeypatch.setattr(doctor_mod, "_DHH", str(home))
+    (tmp_path / "project").mkdir(exist_ok=True)
+
+    fake_model_tools = types.SimpleNamespace(
+        check_tool_availability=lambda *a, **kw: ([], []),
+        TOOLSET_REQUIREMENTS={},
+    )
+    monkeypatch.setitem(sys.modules, "model_tools", fake_model_tools)
+
+    try:
+        from hermes_cli import auth as _auth_mod
+        monkeypatch.setattr(_auth_mod, "get_nous_auth_status", lambda: {})
+        monkeypatch.setattr(_auth_mod, "get_codex_auth_status", lambda: {})
+    except Exception:
+        pass
+
+    buf = io.StringIO()
+    with contextlib.redirect_stdout(buf):
+        doctor_mod.run_doctor(Namespace(fix=False))
+
+    out = buf.getvalue()
+    assert "model.provider 'custom' is not a recognised provider" not in out
+
+
 def test_run_doctor_termux_does_not_mark_browser_available_without_agent_browser(monkeypatch, tmp_path):
     home = tmp_path / ".hermes"
     home.mkdir(parents=True, exist_ok=True)