docs: fix connection keys documentation to say "node names" not "node IDs" (#510) (#511)

The documentation incorrectly stated connection keys should be "node IDs"
when n8n actually requires "node names". This caused workflow creation
failures for AI-generated workflows.

Changes:
- tools-n8n-manager.ts: "Keys are source node names (the name field, not id)"
- n8n-create-workflow.ts: "Keys are source node names (not IDs)"
- Fixed example: "Webhook"/"Slack" instead of "webhook_1"/"slack_1"
- get-template.ts: clarified "source node names"

Closes #510

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

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

Co-authored-by: Romuald Członkowski <romualdczlonkowski@MacBook-Pro-Romuald.local>
Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com>

package.json

@@ -1,6 +1,6 @@
 {
   "name": "n8n-mcp",
-  "version": "2.31.2",
+  "version": "2.31.3",
   "description": "Integration between n8n workflow automation and Model Context Protocol (MCP)",
   "main": "dist/index.js",
   "types": "dist/index.d.ts",