fix(plugins): alias-normalize enable/disable for nested category plugins (follow-up to #41076)

#41076 makes `hermes plugins list` discover nested category plugins (e.g.
observability/nemo_relay). This adds the missing enable/disable mutation path
so those plugins can actually be toggled, and fixes two incomplete-update
breakages on the #41076 base.

Before: `hermes plugins enable nemo_relay` -> "Plugin 'nemo_relay' is not
installed or bundled." (exit 1), because cmd_enable/cmd_disable went through
_plugin_exists(), which only checked top-level plugins/<name>/.

Changes:
- Add _resolve_plugin_key(): resolve a bare manifest/leaf name OR a full
  path-derived key (observability/nemo_relay) to the canonical key the runtime
  loader gates on, reusing #41076's _discover_all_plugins(). A bare leaf name
  ambiguous across two categories resolves to None rather than silently picking
  one.
- cmd_enable/cmd_disable resolve first, persist the canonical key, and drop any
  stale legacy bare-name alias so the enabled/disabled lists can't drift into a
  contradictory state. _plugin_exists delegates to the same resolver.
- Fix #41076 base breakages: _discover_all_plugins now returns 6-tuples, but
  web_server._merged_plugins_hub() still unpacked 5 (ValueError on the
  dashboard plugins-hub endpoint) and several test_plugins_cmd_list.py fixtures
  were still 5-tuples. Both updated; the hub status check is now key-aware.

Verified e2e on the real CLI + runtime loader (isolated HERMES_HOME):
`hermes plugins enable nemo_relay` writes observability/nemo_relay to
config.yaml and the loader then loads it (enabled=True, error=None); a stale
bare-name alias is cleared on disable; the dashboard _merged_plugins_hub() runs
without crashing. Adds resolution + enable/disable tests; full
tests/hermes_cli/test_plugins_cmd* + web_server plugin tests green.

Follow-up to #41076 (#41066). Branched from that PR's head.

tests/hermes_cli/test_plugins_cmd_enable_disable_nested.py

@@ -0,0 +1,193 @@
+"""Tests for nested/alias-normalized enable & disable flows.
+
+Companion to test_plugins_cmd_category_discovery.py. That file covers the
+*listing* side of nested category plugins (issue #41066). These tests cover
+the *mutation* side: `hermes plugins enable/disable` must resolve a bare name
+OR a full path-derived key (e.g. `observability/nemo_relay`) to the canonical
+registry key and write THAT — the same string PluginManager gates on — so a
+nested bundled plugin can actually be toggled.
+"""
+
+import sys  # noqa: F401
+from pathlib import Path
+from unittest.mock import patch
+
+import pytest
+
+
+def _make_plugin_dir(parent: Path, name: str, manifest: dict) -> Path:
+    d = parent / name
+    d.mkdir(parents=True, exist_ok=True)
+    import yaml
+    (d / "plugin.yaml").write_text(yaml.dump(manifest), encoding="utf-8")
+    (d / "__init__.py").write_text("def register(ctx): pass\n", encoding="utf-8")
+    return d
+
+
+def _make_category_plugin(parent: Path, category: str, name: str, manifest: dict) -> Path:
+    return _make_plugin_dir(parent / category, name, manifest)
+
+
+@pytest.fixture
+def nested_plugin_env(tmp_path):
+    """A user-plugins dir containing one nested and one flat plugin, with the
+    bundled dir pointed at an empty path. Returns the tmp_path."""
+    _make_category_plugin(tmp_path, "observability", "nemo_relay", {
+        "name": "nemo_relay", "version": "1.0.0", "description": "relay obs"
+    })
+    _make_plugin_dir(tmp_path, "disk-cleanup", {
+        "name": "disk-cleanup", "version": "1.0.0"
+    })
+    return tmp_path
+
+
+# ---------------------------------------------------------------------------
+# _resolve_plugin_key
+# ---------------------------------------------------------------------------
+
+
+class TestResolvePluginKey:
+    @patch("hermes_cli.plugins.get_bundled_plugins_dir")
+    @patch("hermes_cli.plugins_cmd._plugins_dir")
+    def test_full_key_resolves_to_itself(self, mock_user, mock_bundled, nested_plugin_env):
+        from hermes_cli.plugins_cmd import _resolve_plugin_key
+        mock_user.return_value = nested_plugin_env
+        mock_bundled.return_value = nested_plugin_env / "nonexistent"
+        assert _resolve_plugin_key("observability/nemo_relay") == "observability/nemo_relay"
+
+    @patch("hermes_cli.plugins.get_bundled_plugins_dir")
+    @patch("hermes_cli.plugins_cmd._plugins_dir")
+    def test_bare_leaf_name_resolves_to_key(self, mock_user, mock_bundled, nested_plugin_env):
+        from hermes_cli.plugins_cmd import _resolve_plugin_key
+        mock_user.return_value = nested_plugin_env
+        mock_bundled.return_value = nested_plugin_env / "nonexistent"
+        # "nemo_relay" (bare) must normalize to the path-derived key.
+        assert _resolve_plugin_key("nemo_relay") == "observability/nemo_relay"
+
+    @patch("hermes_cli.plugins.get_bundled_plugins_dir")
+    @patch("hermes_cli.plugins_cmd._plugins_dir")
+    def test_flat_plugin_resolves_to_name(self, mock_user, mock_bundled, nested_plugin_env):
+        from hermes_cli.plugins_cmd import _resolve_plugin_key
+        mock_user.return_value = nested_plugin_env
+        mock_bundled.return_value = nested_plugin_env / "nonexistent"
+        assert _resolve_plugin_key("disk-cleanup") == "disk-cleanup"
+
+    @patch("hermes_cli.plugins.get_bundled_plugins_dir")
+    @patch("hermes_cli.plugins_cmd._plugins_dir")
+    def test_unknown_returns_none(self, mock_user, mock_bundled, nested_plugin_env):
+        from hermes_cli.plugins_cmd import _resolve_plugin_key
+        mock_user.return_value = nested_plugin_env
+        mock_bundled.return_value = nested_plugin_env / "nonexistent"
+        assert _resolve_plugin_key("does-not-exist") is None
+
+    @patch("hermes_cli.plugins.get_bundled_plugins_dir")
+    @patch("hermes_cli.plugins_cmd._plugins_dir")
+    def test_ambiguous_leaf_name_returns_none(self, mock_user, mock_bundled, tmp_path):
+        """Same leaf name under two categories must NOT silently pick one."""
+        from hermes_cli.plugins_cmd import _resolve_plugin_key
+        _make_category_plugin(tmp_path, "image_gen", "openai", {"name": "image-gen-openai"})
+        _make_category_plugin(tmp_path, "model-providers", "openai", {"name": "mp-openai"})
+        mock_user.return_value = tmp_path
+        mock_bundled.return_value = tmp_path / "nonexistent"
+        # Bare "openai" is ambiguous -> None; the full key still resolves.
+        assert _resolve_plugin_key("openai") is None
+        assert _resolve_plugin_key("image_gen/openai") == "image_gen/openai"
+
+
+# ---------------------------------------------------------------------------
+# cmd_enable / cmd_disable — write the canonical key
+# ---------------------------------------------------------------------------
+
+
+class TestEnableDisableNested:
+    @patch("hermes_cli.plugins.get_bundled_plugins_dir")
+    @patch("hermes_cli.plugins_cmd._plugins_dir")
+    @patch("hermes_cli.plugins_cmd._save_disabled_set")
+    @patch("hermes_cli.plugins_cmd._save_enabled_set")
+    @patch("hermes_cli.plugins_cmd._get_disabled_set", return_value=set())
+    @patch("hermes_cli.plugins_cmd._get_enabled_set", return_value=set())
+    def test_enable_bare_name_writes_key(
+        self, mock_en, mock_dis, mock_save_en, mock_save_dis,
+        mock_user, mock_bundled, nested_plugin_env,
+    ):
+        from hermes_cli.plugins_cmd import cmd_enable
+        mock_user.return_value = nested_plugin_env
+        mock_bundled.return_value = nested_plugin_env / "nonexistent"
+
+        cmd_enable("nemo_relay")  # bare name
+
+        saved = mock_save_en.call_args[0][0]
+        # The canonical key — NOT the bare name — must be persisted, because
+        # that is what PluginManager matches when deciding to load.
+        assert "observability/nemo_relay" in saved
+        assert "nemo_relay" not in saved or "observability/nemo_relay" in saved
+
+    @patch("hermes_cli.plugins.get_bundled_plugins_dir")
+    @patch("hermes_cli.plugins_cmd._plugins_dir")
+    @patch("hermes_cli.plugins_cmd._save_disabled_set")
+    @patch("hermes_cli.plugins_cmd._save_enabled_set")
+    @patch("hermes_cli.plugins_cmd._get_disabled_set", return_value=set())
+    @patch("hermes_cli.plugins_cmd._get_enabled_set", return_value=set())
+    def test_enable_full_key_writes_key(
+        self, mock_en, mock_dis, mock_save_en, mock_save_dis,
+        mock_user, mock_bundled, nested_plugin_env,
+    ):
+        from hermes_cli.plugins_cmd import cmd_enable
+        mock_user.return_value = nested_plugin_env
+        mock_bundled.return_value = nested_plugin_env / "nonexistent"
+
+        cmd_enable("observability/nemo_relay")
+        saved = mock_save_en.call_args[0][0]
+        assert "observability/nemo_relay" in saved
+
+    @patch("hermes_cli.plugins.get_bundled_plugins_dir")
+    @patch("hermes_cli.plugins_cmd._plugins_dir")
+    @patch("hermes_cli.plugins_cmd._save_disabled_set")
+    @patch("hermes_cli.plugins_cmd._save_enabled_set")
+    @patch("hermes_cli.plugins_cmd._get_disabled_set", return_value=set())
+    @patch("hermes_cli.plugins_cmd._get_enabled_set", return_value=set())
+    def test_disable_bare_name_writes_key_and_clears_alias(
+        self, mock_en, mock_dis, mock_save_en, mock_save_dis,
+        mock_user, mock_bundled, nested_plugin_env,
+    ):
+        from hermes_cli.plugins_cmd import cmd_disable
+        mock_user.return_value = nested_plugin_env
+        mock_bundled.return_value = nested_plugin_env / "nonexistent"
+        # Simulate an existing config where the plugin was enabled under the
+        # legacy bare name — disabling must clear that too, or the plugin would
+        # keep loading (PluginManager accepts the bare name as well).
+        mock_en.return_value = {"nemo_relay"}
+
+        cmd_disable("nemo_relay")
+        saved_dis = mock_save_dis.call_args[0][0]
+        saved_en = mock_save_en.call_args[0][0]
+        assert "observability/nemo_relay" in saved_dis
+        assert "nemo_relay" not in saved_en  # stale bare alias dropped
+
+    @patch("hermes_cli.plugins.get_bundled_plugins_dir")
+    @patch("hermes_cli.plugins_cmd._plugins_dir")
+    def test_enable_unknown_plugin_exits(self, mock_user, mock_bundled, nested_plugin_env):
+        from hermes_cli.plugins_cmd import cmd_enable
+        mock_user.return_value = nested_plugin_env
+        mock_bundled.return_value = nested_plugin_env / "nonexistent"
+        with pytest.raises(SystemExit):
+            cmd_enable("does-not-exist")
+
+    @patch("hermes_cli.plugins.get_bundled_plugins_dir")
+    @patch("hermes_cli.plugins_cmd._plugins_dir")
+    @patch("hermes_cli.plugins_cmd._save_disabled_set")
+    @patch("hermes_cli.plugins_cmd._save_enabled_set")
+    @patch("hermes_cli.plugins_cmd._get_disabled_set", return_value=set())
+    @patch("hermes_cli.plugins_cmd._get_enabled_set", return_value=set())
+    def test_enable_flat_plugin_unchanged(
+        self, mock_en, mock_dis, mock_save_en, mock_save_dis,
+        mock_user, mock_bundled, nested_plugin_env,
+    ):
+        """Flat plugins keep writing their bare name (key == name) — no regression."""
+        from hermes_cli.plugins_cmd import cmd_enable
+        mock_user.return_value = nested_plugin_env
+        mock_bundled.return_value = nested_plugin_env / "nonexistent"
+
+        cmd_enable("disk-cleanup")
+        saved = mock_save_en.call_args[0][0]
+        assert "disk-cleanup" in saved

tests/hermes_cli/test_plugins_cmd_list.py

@@ -18,9 +18,9 @@ def _args(**kwargs):
 
 def test_filter_plugin_entries_enabled_only():
     entries = [
-        ("disk-cleanup", "2.0.0", "Bundled", "bundled", None),
-        ("web-search-plus", "2.2.0", "Search", "git", None),
-        ("old-plugin", "1.0.0", "Old", "user", None),
+        ("disk-cleanup", "2.0.0", "Bundled", "bundled", None, "disk-cleanup"),
+        ("web-search-plus", "2.2.0", "Search", "git", None, "web-search-plus"),
+        ("old-plugin", "1.0.0", "Old", "user", None, "old-plugin"),
     ]
 
     filtered = plugins_cmd._filter_plugin_entries(
@@ -35,9 +35,9 @@ def test_filter_plugin_entries_enabled_only():
 
 def test_filter_plugin_entries_no_bundled():
     entries = [
-        ("disk-cleanup", "2.0.0", "Bundled", "bundled", None),
-        ("drawthings-grpc", "0.3.0", "Draw Things", "user", None),
-        ("web-search-plus", "2.2.0", "Search", "git", None),
+        ("disk-cleanup", "2.0.0", "Bundled", "bundled", None, "disk-cleanup"),
+        ("drawthings-grpc", "0.3.0", "Draw Things", "user", None, "drawthings-grpc"),
+        ("web-search-plus", "2.2.0", "Search", "git", None, "web-search-plus"),
     ]
 
     filtered = plugins_cmd._filter_plugin_entries(
@@ -52,8 +52,8 @@ def test_filter_plugin_entries_no_bundled():
 
 def test_cmd_list_plain_compact_output(monkeypatch, capsys):
     entries = [
-        ("disk-cleanup", "2.0.0", "Bundled", "bundled", None),
-        ("web-search-plus", "2.2.0", "Search", "git", None),
+        ("disk-cleanup", "2.0.0", "Bundled", "bundled", None, "disk-cleanup"),
+        ("web-search-plus", "2.2.0", "Search", "git", None, "web-search-plus"),
     ]
     monkeypatch.setattr(plugins_cmd, "_discover_all_plugins", lambda: entries)
     monkeypatch.setattr(plugins_cmd, "_get_enabled_set", lambda: {"web-search-plus"})
@@ -69,7 +69,7 @@ def test_cmd_list_plain_compact_output(monkeypatch, capsys):
 
 
 def test_cmd_list_json_output(monkeypatch, capsys):
-    entries = [("web-search-plus", "2.2.0", "Search", "git", None)]
+    entries = [("web-search-plus", "2.2.0", "Search", "git", None, "web-search-plus")]
     monkeypatch.setattr(plugins_cmd, "_discover_all_plugins", lambda: entries)
     monkeypatch.setattr(plugins_cmd, "_get_enabled_set", lambda: {"web-search-plus"})
     monkeypatch.setattr(plugins_cmd, "_get_disabled_set", lambda: set())