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>

src/mcp/tool-docs/templates/get-template.ts

@@ -42,7 +42,7 @@ export const getTemplateDoc: ToolDocumentation = {
   - url: Link to template on n8n.io
   - workflow: Complete workflow JSON with structure:
     - nodes: Array of node objects (id, name, type, typeVersion, position, parameters)
-    - connections: Object mapping source nodes to targets
+    - connections: Object mapping source node names to targets
     - settings: Workflow configuration (timezone, error handling, etc.)
 - usage: Instructions for using the workflow`,
     examples: [