Split risk policy into its own navigation tab.

Move read-only risk control docs to /risk_policy before settings; keep transfers and exports on the settings page.

Co-authored-by: Cursor <cursoragent@cursor.com>

tests/test_instance_embed_lib.py

@@ -28,7 +28,9 @@ def test_embed_tabs_cover_main_nav():
     assert "trade" in EMBED_TABS
     assert "key_monitor" in EMBED_TABS
     assert "records" in EMBED_TABS
+    assert "risk_policy" in EMBED_TABS
     assert "settings" in EMBED_TABS
+    assert path_to_embed_tab("/risk_policy") == "risk_policy"
     assert path_to_embed_tab("/settings") == "settings"