chore: release v2.9.1

- Bumped version from 2.9.0 to 2.9.1
- Updated version badge in README.md
- Added comprehensive changelog entry documenting fixedCollection validation fixes
- Increased test coverage from 79.95% to 80.16% to meet CI requirements
- Added 50 new tests for fixed-collection-validator and console-manager

🤖 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": "2.9.0",
+  "version": "2.9.1",
   "description": "n8n MCP Server Runtime Dependencies Only",
   "private": true,
   "dependencies": {