chore: update n8n to ^1.104.1 and bump version to 2.8.1

- Updated n8n to ^1.104.1
- Updated n8n-core to ^1.103.1
- Updated n8n-workflow to ^1.101.0
- Updated @n8n/n8n-nodes-langchain to ^1.103.1
- Rebuilt node database with 532 nodes
- Sanitized 499 workflow templates
- All 1,182 tests passing (933 unit, 249 integration)
- All validation tests passing
- Built and prepared for npm publish

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

Co-Authored-By: Claude <noreply@anthropic.com>

package.runtime.json

@@ -1,6 +1,6 @@
 {
   "name": "n8n-mcp-runtime",
-  "version": "2.7.22",
+  "version": "2.8.1",
   "description": "n8n MCP Server Runtime Dependencies Only",
   "private": true,
   "dependencies": {