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_subparser_routing_fallback.py

@@ -64,85 +64,3 @@ def _safe_parse(parser, subparsers, argv):
         subparsers.required = False
         return parser.parse_args(argv)
 
-
-class TestSubparserRoutingFallback:
-    """Verify the bpo-9338 defensive routing works for all key cases."""
-
-    def test_direct_subcommand(self):
-        parser, sub = _build_parser()
-        args = _safe_parse(parser, sub, ["model"])
-        assert args.command == "model"
-
-    def test_subcommand_with_flags(self):
-        parser, sub = _build_parser()
-        args = _safe_parse(parser, sub, ["--yolo", "model"])
-        assert args.command == "model"
-        assert args.yolo is True
-
-    def test_bare_hermes_defaults_to_none(self):
-        parser, sub = _build_parser()
-        args = _safe_parse(parser, sub, [])
-        assert args.command is None
-
-    def test_flags_only_defaults_to_none(self):
-        parser, sub = _build_parser()
-        args = _safe_parse(parser, sub, ["--yolo"])
-        assert args.command is None
-        assert args.yolo is True
-
-    def test_continue_flag_alone(self):
-        parser, sub = _build_parser()
-        args = _safe_parse(parser, sub, ["-c"])
-        assert args.command is None
-        assert args.continue_last is True
-
-    def test_continue_with_session_name(self):
-        parser, sub = _build_parser()
-        args = _safe_parse(parser, sub, ["-c", "myproject"])
-        assert args.command is None
-        assert args.continue_last == "myproject"
-
-    def test_continue_with_subcommand_name_as_session(self):
-        """Edge case: session named 'model' — should be treated as session name, not subcommand."""
-        parser, sub = _build_parser()
-        args = _safe_parse(parser, sub, ["-c", "model"])
-        assert args.command is None
-        assert args.continue_last == "model"
-
-    def test_continue_with_session_then_subcommand(self):
-        parser, sub = _build_parser()
-        args = _safe_parse(parser, sub, ["-c", "myproject", "model"])
-        assert args.command == "model"
-        assert args.continue_last == "myproject"
-
-    def test_chat_with_query(self):
-        parser, sub = _build_parser()
-        args = _safe_parse(parser, sub, ["chat", "-q", "hello"])
-        assert args.command == "chat"
-        assert args.query == "hello"
-
-    def test_resume_flag(self):
-        parser, sub = _build_parser()
-        args = _safe_parse(parser, sub, ["-r", "abc123"])
-        assert args.command is None
-        assert args.resume == "abc123"
-
-    def test_resume_with_subcommand(self):
-        parser, sub = _build_parser()
-        args = _safe_parse(parser, sub, ["-r", "abc123", "chat"])
-        assert args.command == "chat"
-        assert args.resume == "abc123"
-
-    def test_skills_flag_with_subcommand(self):
-        parser, sub = _build_parser()
-        args = _safe_parse(parser, sub, ["-s", "myskill", "chat"])
-        assert args.command == "chat"
-        assert args.skills == ["myskill"]
-
-    def test_all_flags_with_subcommand(self):
-        parser, sub = _build_parser()
-        args = _safe_parse(parser, sub, ["--yolo", "-w", "-s", "myskill", "model"])
-        assert args.command == "model"
-        assert args.yolo is True
-        assert args.worktree is True
-        assert args.skills == ["myskill"]