revert(web): remove keyless Parallel search fallback (#46350)

Remove the free Parallel Search MCP path and restore the keyed Parallel backend behavior from before it was introduced.

Also drops the keyless fallback registration/display labeling tests and returns the Parallel SDK pin to the prior version.

tests/hermes_cli/test_tools_config.py

@@ -975,19 +975,6 @@ def test_toolset_has_keys_treats_no_key_providers_as_configured():
     assert _toolset_has_keys("computer_use", config) is True
 
 
-def test_web_no_prompt_when_usable_keyless():
-    """Fresh install: web works via the free Parallel MCP, so enabling the web
-    toolset should not force provider setup."""
-    with patch("tools.web_tools.check_web_api_key", return_value=True):
-        assert _toolset_needs_configuration_prompt("web", {}) is False
-
-
-def test_web_no_prompt_when_extract_backend_is_extract_capable():
-    with patch("tools.web_tools.check_web_api_key", return_value=True):
-        cfg = {"web": {"extract_backend": "parallel"}}
-        assert _toolset_needs_configuration_prompt("web", cfg) is False
-
-
 def test_computer_use_needs_configuration_when_cua_driver_post_setup_pending():
     """No-key providers can still need setup when their post_setup is unsatisfied.