fix(rolegraph-py): address code review findings

- Simplify __repr__ to avoid calling get_graph_stats() on every repr
  (was O(n) for large graphs, now just shows role + document count)
- Fix LogicalOperator type stub to use LogicalOperator type instead of int
- Strengthen test_is_all_terms_connected_by_path to assert expected True
  for co-occurring terms instead of only checking return type

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: AlexMikhalev

crates/terraphim_rolegraph_py/python/terraphim_rolegraph/__init__.pyi

@@ -77,8 +77,8 @@ class GraphStats:
 class LogicalOperator:
     """Logical operator for combining search terms."""
 
-    And: int
-    Or: int
+    And: "LogicalOperator"
+    Or: "LogicalOperator"
 
 class RoleGraph:
     """A knowledge graph for a specific role."""

crates/terraphim_rolegraph_py/python/tests/test_rolegraph.py

@@ -121,11 +121,16 @@ def test_find_matching_node_ids(self, populated_rolegraph):
         assert len(ids) >= 2
 
     def test_is_all_terms_connected_by_path(self, populated_rolegraph):
-        # Terms that co-occur in the same document should be connected
-        result = populated_rolegraph.is_all_terms_connected_by_path(
+        # "machine learning" and "deep learning" co-occur in doc1, so they are connected
+        assert populated_rolegraph.is_all_terms_connected_by_path(
             "machine learning deep learning"
+        ) is True
+        # A term not in the thesaurus produces no nodes, so connectivity is vacuously true;
+        # verify a single known term still returns a bool
+        assert isinstance(
+            populated_rolegraph.is_all_terms_connected_by_path("machine learning"),
+            bool,
         )
-        assert isinstance(result, bool)
 
 
 class TestGraphStats:

crates/terraphim_rolegraph_py/src/lib.rs

@@ -477,13 +477,10 @@ impl PyRoleGraph {
     // -- Dunder methods -----------------------------------------------------
 
     fn __repr__(&self) -> String {
-        let stats = self.inner.get_graph_stats();
         format!(
-            "RoleGraph(role='{}', nodes={}, edges={}, documents={})",
+            "RoleGraph(role='{}', documents={})",
             self.inner.role.original,
-            stats.node_count,
-            stats.edge_count,
-            stats.document_count
+            self.inner.document_count()
         )
     }