fix: Neo4j DateTime serialization + match all edge types

- Convert Neo4j DateTime objects to strings via _safe_str() helper
- Query all edge types (RELATES_TO + MENTIONS), not just RELATES_TO
- Fix get_node_edges to match any relationship type

Generated with [Claude Code](https://claude.ai/code)
via [Happy](https://happy.engineering)

Co-Authored-By: Claude <noreply@anthropic.com>
Co-Authored-By: Happy <yesreply@happy.engineering>

backend/app/services/graphiti_client.py

@@ -20,6 +20,13 @@ from ..utils.logger import get_logger
 logger = get_logger('foresight.graphiti_client')
 
 
+def _safe_str(val):
+    """Convert any value to JSON-safe string, handling Neo4j DateTime etc."""
+    if val is None:
+        return None
+    return str(val)
+
+
 from graphiti_core.embedder.client import EmbedderClient
 
 
@@ -354,8 +361,8 @@ class GraphitiClient:
                     name=n.get("name", ""),
                     labels=labels,
                     summary=n.get("summary", ""),
-                    attributes=dict(n) if n else {},
+                    attributes={k: _safe_str(v) for k, v in dict(n).items()} if n else {},
-                    created_at=str(n.get("created_at", "")) if n.get("created_at") else None,
+                    created_at=_safe_str(n.get("created_at")),
                 ))
             return nodes
 
@@ -364,9 +371,9 @@ class GraphitiClient:
         with self._driver.session() as session:
             result = session.run(
                 """
-                MATCH (a)-[r:RELATES_TO]->(b)
+                MATCH (a)-[r]->(b)
                 WHERE r.group_id = $gid
-                RETURN r, a.uuid as source_uuid, b.uuid as target_uuid
+                RETURN r, type(r) as rtype, a.uuid as source_uuid, b.uuid as target_uuid
                 """,
                 gid=graph_id,
             )
@@ -379,11 +386,11 @@ class GraphitiClient:
                     fact=r.get("fact", ""),
                     source_node_uuid=str(record["source_uuid"] or ""),
                     target_node_uuid=str(record["target_uuid"] or ""),
-                    attributes=dict(r) if r else {},
+                    attributes={k: _safe_str(v) for k, v in dict(r).items()} if r else {},
-                    created_at=str(r.get("created_at", "")) if r.get("created_at") else None,
+                    created_at=_safe_str(r.get("created_at")),
-                    valid_at=str(r.get("valid_at", "")) if r.get("valid_at") else None,
+                    valid_at=_safe_str(r.get("valid_at")),
-                    invalid_at=str(r.get("invalid_at", "")) if r.get("invalid_at") else None,
+                    invalid_at=_safe_str(r.get("invalid_at")),
-                    expired_at=str(r.get("expired_at", "")) if r.get("expired_at") else None,
+                    expired_at=_safe_str(r.get("expired_at")),
                 ))
             return edges
 
@@ -407,8 +414,8 @@ class GraphitiClient:
                 name=n.get("name", ""),
                 labels=labels,
                 summary=n.get("summary", ""),
-                attributes=dict(n) if n else {},
+                attributes={k: _safe_str(v) for k, v in dict(n).items()} if n else {},
-                created_at=str(n.get("created_at", "")) if n.get("created_at") else None,
+                created_at=_safe_str(n.get("created_at")),
             )
 
     def get_node_edges(self, node_uuid: str) -> List[GraphitiEdge]:
@@ -416,7 +423,7 @@ class GraphitiClient:
         with self._driver.session() as session:
             result = session.run(
                 """
-                MATCH (a)-[r:RELATES_TO]-(b)
+                MATCH (a)-[r]-(b)
                 WHERE a.uuid = $uuid
                 RETURN r,
                        CASE WHEN startNode(r) = a THEN a.uuid ELSE b.uuid END as source_uuid,