fix: remove historical migration info from tools documentation (v2.26.5) (#448)

- Remove "Replaces X, Y, Z..." sentences from full.description in:
  - get_node, validate_node, search_templates, n8n_executions, n8n_get_workflow
- Remove version/issue references from n8n_update_partial_workflow
- Clean up consolidation comments in index.ts
- Documentation now starts directly with functional content
- Estimated token savings: ~128 tokens per full documentation request

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

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

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

package.json

@@ -1,6 +1,6 @@
 {
   "name": "n8n-mcp",
-  "version": "2.26.4",
+  "version": "2.26.5",
   "description": "Integration between n8n workflow automation and Model Context Protocol (MCP)",
   "main": "dist/index.js",
   "types": "dist/index.d.ts",