feat: return navigation disabled as sequence metadata (#34049)

Return navigation disabled as sequence metadata when Hide From TOC
is enabled, so the student cannot navigate to another sequences in
the course outline.
https://openedx.atlassian.net/wiki/spaces/OEPM/pages/3853975595/Feature+Enhancement+Proposal+Hide+Sections+from+course+outline

xmodule/seq_block.py

@@ -376,8 +376,19 @@ def get_metadata(self, view=STUDENT_VIEW, context=None):
         meta['display_name'] = self.display_name_with_default
         meta['format'] = getattr(self, 'format', '')
         meta['is_hidden_after_due'] = is_hidden_after_due
+        meta['navigation_disabled'] = self.is_sequence_navigation_disabled()
         return meta
 
+    def is_sequence_navigation_disabled(self):
+        """
+        Returns whether the navigation to other sequences is disabled.
+
+        As of today, this is used to disable the navigation to other sequences when the
+        current sequence is configured as Hide from Table of Contents. But it can be
+        extended to other use cases in the future.
+        """
+        return getattr(self, "hide_from_toc", False)
+
     @classmethod
     def verify_current_content_visibility(cls, date, hide_after_date):
         """

xmodule/tests/test_sequence.py

@@ -443,6 +443,15 @@ def test_get_metadata(self):
         assert metadata['tag'] == 'sequential'
         assert metadata['display_name'] == self.sequence_3_1.display_name_with_default
 
+    def test_get_metadata_navigation_disabled(self):
+        """Test that the sequence metadata is returned correctly when navigation is disabled"""
+        self.sequence_3_1.hide_from_toc = True
+        metadata = self.sequence_3_1.get_metadata()
+        assert len(metadata['items']) == 3
+        assert metadata['tag'] == 'sequential'
+        assert metadata['display_name'] == self.sequence_3_1.display_name_with_default
+        assert metadata['navigation_disabled'] is True
+
     @override_settings(FIELD_OVERRIDE_PROVIDERS=(
         'openedx.features.content_type_gating.field_override.ContentTypeGatingFieldOverride',
     ))