fix: resolve CI test failures — add missing functions, fix stale tests (#9483)

Production fixes:
- Add clear_session_context() to hermes_logging.py (fixes 48 teardown errors)
- Add clear_session() to tools/approval.py (fixes 9 setup errors)
- Add SyncError M_UNKNOWN_TOKEN check to Matrix _sync_loop (bug fix)
- Fall back to inline api_key in named custom providers when key_env
  is absent (runtime_provider.py)

Test fixes:
- test_memory_user_id: use builtin+external provider pair, fix honcho
  peer_name override test to match production behavior
- test_display_config: remove TestHelpers for non-existent functions
- test_auxiliary_client: fix OAuth tokens to match _is_oauth_token
  patterns, replace get_vision_auxiliary_client with resolve_vision_provider_client
- test_cli_interrupt_subagent: add missing _execution_thread_id attr
- test_compress_focus: add model/provider/api_key/base_url/api_mode
  to mock compressor
- test_auth_provider_gate: add autouse fixture to clean Anthropic env
  vars that leak from CI secrets
- test_opencode_go_in_model_list: accept both 'built-in' and 'hermes'
  source (models.dev API unavailable in CI)
- test_email: verify email Platform enum membership instead of source
  inspection (build_channel_directory now uses dynamic enum loop)
- test_feishu: add bot_added/bot_deleted handler mocks to _Builder
- test_ws_auth_retry: add AsyncMock for sync_store.get_next_batch,
  add _pending_megolm and _joined_rooms to Matrix adapter mocks
- test_restart_drain: monkeypatch-delete INVOCATION_ID (systemd sets
  this in CI, changing the restart call signature)
- test_session_hygiene: add user_id to SessionSource
- test_session_env: use relative baseline for contextvar clear check
  (pytest-xdist workers share context)

tests/gateway/test_display_config.py

@@ -220,41 +220,6 @@ class TestPlatformDefaults:
         assert resolve_display_setting({}, "telegram", "streaming") is None
 
 
-# ---------------------------------------------------------------------------
-# get_effective_display / get_platform_defaults
-# ---------------------------------------------------------------------------
-
-class TestHelpers:
-    """Helper functions return correct composite results."""
-
-    def test_get_effective_display_merges_correctly(self):
-        from gateway.display_config import get_effective_display
-
-        config = {
-            "display": {
-                "tool_progress": "new",
-                "show_reasoning": True,
-                "platforms": {
-                    "telegram": {"tool_progress": "verbose"},
-                },
-            }
-        }
-        eff = get_effective_display(config, "telegram")
-        assert eff["tool_progress"] == "verbose"  # platform override
-        assert eff["show_reasoning"] is True       # global
-        assert "tool_preview_length" in eff        # default filled in
-
-    def test_get_platform_defaults_returns_dict(self):
-        from gateway.display_config import get_platform_defaults
-
-        defaults = get_platform_defaults("telegram")
-        assert "tool_progress" in defaults
-        assert "show_reasoning" in defaults
-        # Returns a new dict (not the shared tier dict)
-        defaults["tool_progress"] = "changed"
-        assert get_platform_defaults("telegram")["tool_progress"] != "changed"
-
-
 # ---------------------------------------------------------------------------
 # Config migration: tool_progress_overrides → display.platforms
 # ---------------------------------------------------------------------------