Fix datetime comparison errors by normalizing to UTC (#988)

* Fix datetime comparison errors by normalizing to UTC

Applied ensure_utc() to all datetime comparisons in edge_operations.py to prevent TypeError when comparing timezone-naive and timezone-aware datetimes. Removed redundant tzinfo checks since ensure_utc() handles both None and naive datetimes.

Fixed comparisons at:
- Lines 419, 423: resolve_edge_contradictions function
- Line 430: resolve_edge_contradictions function
- Line 627: resolve_extracted_edge function (removed redundant tzinfo checks)

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

* Update uv.lock

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

* Fix sorting with mixed timezone-aware/naive datetimes

Normalize datetime to UTC in sort key to prevent TypeError when comparing mixed timezone-aware and timezone-naive datetimes during sorting.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

---------

Co-authored-by: Claude <noreply@anthropic.com>

graphiti_core/utils/maintenance/edge_operations.py

@@ -413,21 +413,26 @@ def resolve_edge_contradictions(
     invalidated_edges: list[EntityEdge] = []
     for edge in invalidation_candidates:
         # (Edge invalid before new edge becomes valid) or (new edge invalid before edge becomes valid)
+        edge_invalid_at_utc = ensure_utc(edge.invalid_at)
+        resolved_edge_valid_at_utc = ensure_utc(resolved_edge.valid_at)
+        edge_valid_at_utc = ensure_utc(edge.valid_at)
+        resolved_edge_invalid_at_utc = ensure_utc(resolved_edge.invalid_at)
+
         if (
-            edge.invalid_at is not None
+            edge_invalid_at_utc is not None
-            and resolved_edge.valid_at is not None
+            and resolved_edge_valid_at_utc is not None
-            and edge.invalid_at <= resolved_edge.valid_at
+            and edge_invalid_at_utc <= resolved_edge_valid_at_utc
         ) or (
-            edge.valid_at is not None
+            edge_valid_at_utc is not None
-            and resolved_edge.invalid_at is not None
+            and resolved_edge_invalid_at_utc is not None
-            and resolved_edge.invalid_at <= edge.valid_at
+            and resolved_edge_invalid_at_utc <= edge_valid_at_utc
         ):
             continue
         # New edge invalidates edge
         elif (
-            edge.valid_at is not None
+            edge_valid_at_utc is not None
-            and resolved_edge.valid_at is not None
+            and resolved_edge_valid_at_utc is not None
-            and edge.valid_at < resolved_edge.valid_at
+            and edge_valid_at_utc < resolved_edge_valid_at_utc
         ):
             edge.invalid_at = resolved_edge.valid_at
             edge.expired_at = edge.expired_at if edge.expired_at is not None else utc_now()
@@ -619,14 +624,14 @@ async def resolve_extracted_edge(
 
     # Determine if the new_edge needs to be expired
     if resolved_edge.expired_at is None:
-        invalidation_candidates.sort(key=lambda c: (c.valid_at is None, c.valid_at))
+        invalidation_candidates.sort(key=lambda c: (c.valid_at is None, ensure_utc(c.valid_at)))
         for candidate in invalidation_candidates:
+            candidate_valid_at_utc = ensure_utc(candidate.valid_at)
+            resolved_edge_valid_at_utc = ensure_utc(resolved_edge.valid_at)
             if (
-                candidate.valid_at
+                candidate_valid_at_utc is not None
-                and resolved_edge.valid_at
+                and resolved_edge_valid_at_utc is not None
-                and candidate.valid_at.tzinfo
+                and candidate_valid_at_utc > resolved_edge_valid_at_utc
-                and resolved_edge.valid_at.tzinfo
-                and candidate.valid_at > resolved_edge.valid_at
             ):
                 # Expire new edge since we have information about more recent events
                 resolved_edge.invalid_at = candidate.valid_at

uv.lock

@@ -783,7 +783,7 @@ wheels = [
 
 [[package]]
 name = "graphiti-core"
-version = "0.22.0rc4"
+version = "0.22.0rc5"
 source = { editable = "." }
 dependencies = [
     { name = "diskcache" },