feat: Add OurDigital custom skills package (10 skills)

Complete implementation of OurDigital skills with dual-platform support
(Claude Desktop + Claude Code) following standardized structure.

Skills created:
- 01-ourdigital-brand-guide: Brand reference & style guidelines
- 02-ourdigital-blog: Korean blog drafts (blog.ourdigital.org)
- 03-ourdigital-journal: English essays (journal.ourdigital.org)
- 04-ourdigital-research: Research prompts & workflows
- 05-ourdigital-document: Notion-to-presentation pipeline
- 06-ourdigital-designer: Visual/image prompt generation
- 07-ourdigital-ad-manager: Ad copywriting & keyword research
- 08-ourdigital-trainer: Training materials & workshop planning
- 09-ourdigital-backoffice: Quotes, proposals, cost analysis
- 10-ourdigital-skill-creator: Meta skill for creating new skills

Features:
- YAML frontmatter with "ourdigital" or "our" prefix triggers
- Standardized directory structure (code/, desktop/, shared/, docs/)
- Shared environment setup (_ourdigital-shared/)
- Comprehensive reference documentation
- Cross-skill integration support

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

custom-skills/19-seo-technical-audit/code/scripts/requirements.txt

@@ -0,0 +1,17 @@
+# 10-seo-technical-audit dependencies
+# Install: pip install -r requirements.txt
+
+# Web Scraping & Parsing
+lxml>=5.1.0
+beautifulsoup4>=4.12.0
+requests>=2.31.0
+aiohttp>=3.9.0
+
+# Async & Retry
+tenacity>=8.2.0
+tqdm>=4.66.0
+
+# Environment & CLI
+python-dotenv>=1.0.0
+rich>=13.7.0
+typer>=0.9.0