fix: memory leak in SSE session reset (#542) (#544)

When SSE sessions are recreated every 5 minutes, the old session's MCP
server was not being closed, causing:
- SimpleCache cleanup timer continuing to run indefinitely
- Database connections remaining open
- Cached data (~50-100MB per session) persisting in memory

Added server.close() call before transport.close() in resetSessionSSE(),
mirroring the existing cleanup pattern in removeSession().

Fixes #542

Conceived by Romuald Członkowski - https://www.aiadvisors.pl/en

Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com>

package.json

@@ -1,6 +1,6 @@
 {
   "name": "n8n-mcp",
-  "version": "2.33.3",
+  "version": "2.33.4",
   "description": "Integration between n8n workflow automation and Model Context Protocol (MCP)",
   "main": "dist/index.js",
   "types": "dist/index.d.ts",