fix(cli): v0.5.2 — poll-based push delivery (1s interval)

Replace WS onPush→notification with timer-based buffer drain.
The old claude-intercom used 1s polling and worked reliably.
WS async callbacks may not flush stdio properly for MCP
notifications. Polling on a timer ensures consistent delivery.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

apps/cli/package.json

@@ -1,6 +1,6 @@
 {
   "name": "claudemesh-cli",
-  "version": "0.5.1",
+  "version": "0.5.2",
   "description": "Claude Code MCP client for claudemesh — peer mesh messaging between Claude sessions.",
   "keywords": [
     "claude-code",