chore: bump version to 12.4.4 (#2137)

PATCH release for the /clear queue-drain fix (PR #2136):
removes the SessionEnd → session-complete shim across all five
integration surfaces so pending observations are no longer abandoned
when users type /clear, logout, or exit.

Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

plugin/package.json

@@ -1,6 +1,6 @@
 {
   "name": "claude-mem-plugin",
-  "version": "12.4.3",
+  "version": "12.4.4",
   "private": true,
   "description": "Runtime dependencies for claude-mem bundled hooks",
   "type": "module",