fix: Use lowercase-with-hyphens skill names for Claude.ai compatibility

Fix skill names in SKILL.md frontmatter to comply with Claude.ai requirements:
"Skill name in SKILL.md can only contain lowercase letters, numbers, and hyphens."

## Changes

Updated skill names from "Title Case With Spaces" to "lowercase-with-hyphens":

1. "n8n Expression Syntax" → "n8n-expression-syntax"
2. "n8n MCP Tools Expert" → "n8n-mcp-tools-expert"
3. "n8n Workflow Patterns" → "n8n-workflow-patterns"
4. "n8n Validation Expert" → "n8n-validation-expert"
5. "n8n Node Configuration" → "n8n-node-configuration"

## Files Modified

- skills/n8n-expression-syntax/SKILL.md
- skills/n8n-mcp-tools-expert/SKILL.md
- skills/n8n-workflow-patterns/SKILL.md
- skills/n8n-validation-expert/SKILL.md
- skills/n8n-node-configuration/SKILL.md

## Distribution Packages

Regenerated all distribution zip files with corrected SKILL.md:
- dist/n8n-expression-syntax-v1.0.0.zip
- dist/n8n-mcp-tools-expert-v1.0.0.zip
- dist/n8n-workflow-patterns-v1.0.0.zip
- dist/n8n-validation-expert-v1.0.0.zip
- dist/n8n-node-configuration-v1.0.0.zip
- dist/n8n-mcp-skills-claude-code-v1.0.0.zip

Skills can now be uploaded to Claude.ai without naming errors.

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

Co-Authored-By: Claude <noreply@anthropic.com>
Conceived by Romuald Członkowski - https://www.aiadvisors.pl/en

skills/n8n-workflow-patterns/SKILL.md

@@ -1,5 +1,5 @@
 ---
-name: n8n Workflow Patterns
+name: n8n-workflow-patterns
 description: Proven workflow architectural patterns from real n8n workflows. Use when building new workflows, designing workflow structure, choosing workflow patterns, planning workflow architecture, or asking about webhook processing, HTTP API integration, database operations, AI agent workflows, or scheduled tasks.
 ---