fix(openviking): add atexit safety net for session commit

Ensures pending sessions are committed on process exit even if
shutdown_memory_provider is never called (gateway crash, SIGKILL,
or exception in _async_flush_memories preventing shutdown).

Also reorders on_session_end to wait for the pending sync thread
before checking turn_count, so the last turn's messages are flushed.

Based on PR #4919 by dagbs.

plugins/memory/openviking/__init__.py

@@ -23,6 +23,7 @@ Capabilities:
 
 from __future__ import annotations
 
+import atexit
 import json
 import logging
 import os
@@ -37,6 +38,30 @@ _DEFAULT_ENDPOINT = "http://127.0.0.1:1933"
 _TIMEOUT = 30.0
 
 
+# ---------------------------------------------------------------------------
+# Process-level atexit safety net — ensures pending sessions are committed
+# even if shutdown_memory_provider is never called (e.g. gateway crash,
+# SIGKILL, or exception in _async_flush_memories preventing shutdown).
+# ---------------------------------------------------------------------------
+_last_active_provider: Optional["OpenVikingMemoryProvider"] = None
+
+
+def _atexit_commit_sessions():
+    """Fire on_session_end for the last active provider on process exit."""
+    global _last_active_provider
+    provider = _last_active_provider
+    if provider is None:
+        return
+    _last_active_provider = None
+    try:
+        provider.on_session_end([])
+    except Exception:
+        pass  # best-effort at shutdown time
+
+
+atexit.register(_atexit_commit_sessions)
+
+
 # ---------------------------------------------------------------------------
 # HTTP helper — uses httpx to avoid requiring the openviking SDK
 # ---------------------------------------------------------------------------
@@ -277,6 +302,10 @@ class OpenVikingMemoryProvider(MemoryProvider):
             logger.warning("httpx not installed — OpenViking plugin disabled")
             self._client = None
 
+        # Register as the last active provider for atexit safety net
+        global _last_active_provider
+        _last_active_provider = self
+
     def system_prompt_block(self) -> str:
         if not self._client:
             return ""
@@ -387,13 +416,18 @@ class OpenVikingMemoryProvider(MemoryProvider):
         OpenViking automatically extracts 6 categories of memories:
         profile, preferences, entities, events, cases, and patterns.
         """
-        if not self._client or self._turn_count == 0:
+        if not self._client:
             return
 
-        # Wait for any pending sync to finish first
+        # Wait for any pending sync to finish first — do this before the
+        # turn_count check so the last turn's messages are flushed even if
+        # the count hasn't been incremented yet.
         if self._sync_thread and self._sync_thread.is_alive():
             self._sync_thread.join(timeout=10.0)
 
+        if self._turn_count == 0:
+            return
+
         try:
             self._client.post(f"/api/v1/sessions/{self._session_id}/commit")
             logger.info("OpenViking session %s committed (%d turns)", self._session_id, self._turn_count)
@@ -449,6 +483,10 @@ class OpenVikingMemoryProvider(MemoryProvider):
         for t in (self._sync_thread, self._prefetch_thread):
             if t and t.is_alive():
                 t.join(timeout=5.0)
+        # Clear atexit reference so it doesn't double-commit
+        global _last_active_provider
+        if _last_active_provider is self:
+            _last_active_provider = None
 
     # -- Tool implementations ------------------------------------------------