test: remove 169 change-detector tests across 21 files (#11472)

First pass of test-suite reduction to address flaky CI and bloat.

Removed tests that fall into these change-detector patterns:

1. Source-grep tests (tests/gateway/test_feishu.py, test_email.py): tests
   that call inspect.getsource() on production modules and grep for string
   literals. Break on any refactor/rename even when behavior is correct.

2. Platform enum tautologies (every gateway/test_X.py): assertions like
   `Platform.X.value == 'x'` duplicated across ~9 adapter test files.

3. Toolset/PLATFORM_HINTS/setup-wizard registry-presence checks: tests that
   only verify a key exists in a dict. Data-layout tests, not behavior.

4. Argparse wiring tests (test_argparse_flag_propagation, test_subparser_routing
   _fallback): tests that do parser.parse_args([...]) then assert args.field.
   Tests Python's argparse, not our code.

5. Pure dispatch tests (test_plugins_cmd.TestPluginsCommandDispatch): patch
   cmd_X, call plugins_command with matching action, assert mock called.
   Tests the if/elif chain, not behavior.

6. Kwarg-to-mock verification (test_auxiliary_client ~45 tests,
   test_web_tools_config, test_gemini_cloudcode, test_retaindb_plugin): tests
   that mock the external API client, call our function, and assert exact
   kwargs. Break on refactor even when behavior is preserved.

7. Schedule-internal "function-was-called" tests (acp/test_server scheduling
   tests): tests that patch own helper method, then assert it was called.

Kept behavioral tests throughout: error paths (pytest.raises), security
tests (path traversal, SSRF, redaction), message alternation invariants,
provider API format conversion, streaming logic, memory contract, real
config load/merge tests.

Net reduction: 169 tests removed. 38 empty classes cleaned up.

Collected before: 12,522 tests
Collected after:  12,353 tests

tests/hermes_cli/test_plugins_cmd.py

@@ -126,59 +126,6 @@ class TestRepoNameFromUrl:
 # ── plugins_command dispatch ──────────────────────────────────────────────
 
 
-class TestPluginsCommandDispatch:
-    """Verify alias routing in plugins_command()."""
-
-    def _make_args(self, action, **extras):
-        args = MagicMock()
-        args.plugins_action = action
-        for k, v in extras.items():
-            setattr(args, k, v)
-        return args
-
-    @patch("hermes_cli.plugins_cmd.cmd_remove")
-    def test_rm_alias(self, mock_remove):
-        args = self._make_args("rm", name="some-plugin")
-        plugins_command(args)
-        mock_remove.assert_called_once_with("some-plugin")
-
-    @patch("hermes_cli.plugins_cmd.cmd_remove")
-    def test_uninstall_alias(self, mock_remove):
-        args = self._make_args("uninstall", name="some-plugin")
-        plugins_command(args)
-        mock_remove.assert_called_once_with("some-plugin")
-
-    @patch("hermes_cli.plugins_cmd.cmd_list")
-    def test_ls_alias(self, mock_list):
-        args = self._make_args("ls")
-        plugins_command(args)
-        mock_list.assert_called_once()
-
-    @patch("hermes_cli.plugins_cmd.cmd_toggle")
-    def test_none_falls_through_to_toggle(self, mock_toggle):
-        args = self._make_args(None)
-        plugins_command(args)
-        mock_toggle.assert_called_once()
-
-    @patch("hermes_cli.plugins_cmd.cmd_install")
-    def test_install_dispatches(self, mock_install):
-        args = self._make_args("install", identifier="owner/repo", force=False)
-        plugins_command(args)
-        mock_install.assert_called_once_with("owner/repo", force=False)
-
-    @patch("hermes_cli.plugins_cmd.cmd_update")
-    def test_update_dispatches(self, mock_update):
-        args = self._make_args("update", name="foo")
-        plugins_command(args)
-        mock_update.assert_called_once_with("foo")
-
-    @patch("hermes_cli.plugins_cmd.cmd_remove")
-    def test_remove_dispatches(self, mock_remove):
-        args = self._make_args("remove", name="bar")
-        plugins_command(args)
-        mock_remove.assert_called_once_with("bar")
-
-
 # ── _read_manifest ────────────────────────────────────────────────────────