fix(memory): strip extra properties when loading entities from JSONL

When loading entities and relations from JSONL files, the parsed JSON
objects included extra properties like `type` (used for discriminating
entity vs relation) and any other custom fields. These extra properties
leaked into the Entity/Relation objects, causing MCP schema validation
errors (-32602 Invalid params) when outputSchema validation is enabled.

The fix explicitly extracts only the schema-defined properties (name,
entityType, observations for entities; from, to, relationType for
relations) instead of casting the entire parsed object.

Fixes #3144

Author: cardmagic

src/memory/__tests__/knowledge-graph.test.ts

@@ -360,6 +360,40 @@ describe('KnowledgeGraphManager', () => {
     });
   });
 
+  describe('loading entities with extra properties', () => {
+    it('should strip extra properties from entities when loading (issue #3144)', async () => {
+      // Write JSONL file directly with extra properties (simulating manual edits or legacy data)
+      const jsonlContent = [
+        JSON.stringify({ type: "entity", name: "Test", entityType: "test", observations: ["obs1"], custom_id: "xyz-123", extra_field: true }),
+        JSON.stringify({ type: "relation", from: "Test", to: "Test", relationType: "self", extra_prop: "should be stripped" })
+      ].join('\n');
+      await fs.writeFile(testFilePath, jsonlContent);
+
+      const graph = await manager.readGraph();
+
+      // Entities should only have the schema-defined properties
+      expect(graph.entities).toHaveLength(1);
+      expect(graph.entities[0]).toEqual({
+        name: "Test",
+        entityType: "test",
+        observations: ["obs1"]
+      });
+      expect(graph.entities[0]).not.toHaveProperty('type');
+      expect(graph.entities[0]).not.toHaveProperty('custom_id');
+      expect(graph.entities[0]).not.toHaveProperty('extra_field');
+
+      // Relations should only have the schema-defined properties
+      expect(graph.relations).toHaveLength(1);
+      expect(graph.relations[0]).toEqual({
+        from: "Test",
+        to: "Test",
+        relationType: "self"
+      });
+      expect(graph.relations[0]).not.toHaveProperty('type');
+      expect(graph.relations[0]).not.toHaveProperty('extra_prop');
+    });
+  });
+
   describe('file persistence', () => {
     it('should persist data across manager instances', async () => {
       await manager.createEntities([

src/memory/index.ts

@@ -74,8 +74,20 @@ export class KnowledgeGraphManager {
       const lines = data.split("\n").filter(line => line.trim() !== "");
       return lines.reduce((graph: KnowledgeGraph, line) => {
         const item = JSON.parse(line);
-        if (item.type === "entity") graph.entities.push(item as Entity);
-        if (item.type === "relation") graph.relations.push(item as Relation);
+        if (item.type === "entity") {
+          graph.entities.push({
+            name: item.name,
+            entityType: item.entityType,
+            observations: item.observations
+          });
+        }
+        if (item.type === "relation") {
+          graph.relations.push({
+            from: item.from,
+            to: item.to,
+            relationType: item.relationType
+          });
+        }
         return graph;
       }, { entities: [], relations: [] });
     } catch (error) {