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/05-ourdigital-document/code/CLAUDE.md

@@ -0,0 +1,82 @@
+# CLAUDE.md
+
+## Overview
+
+Notion-to-presentation workflow. Transforms research content into branded PowerPoint/Figma presentations.
+
+## Quick Start
+
+```bash
+# Full automated workflow
+python scripts/run_workflow.py --notion-url [URL] --output presentation.pptx
+
+# Step-by-step
+python scripts/extract_notion.py [URL] > research.json
+python scripts/synthesize_content.py research.json > synthesis.json
+python scripts/apply_brand.py synthesis.json --output presentation.pptx
+```
+
+## Scripts
+
+| Script | Purpose |
+|--------|---------|
+| `run_workflow.py` | Orchestrate full pipeline |
+| `extract_notion.py` | Extract content from Notion pages |
+| `synthesize_content.py` | Analyze and structure content |
+| `apply_brand.py` | Apply corporate styling |
+
+## Workflow Pipeline
+
+```
+extract_notion.py → synthesize_content.py → apply_brand.py
+     ↓                    ↓                      ↓
+ research.json       synthesis.json         presentation.pptx
+```
+
+## Extract Notion
+
+```bash
+# Single page
+python scripts/extract_notion.py notion://page/abc123 > research.json
+
+# Database query
+python scripts/extract_notion.py notion://database/def456 --filter "Status=Done"
+```
+
+## Synthesize Content
+
+```bash
+# Generate slide structure
+python scripts/synthesize_content.py research.json > synthesis.json
+
+# With presentation type
+python scripts/synthesize_content.py research.json \
+  --type executive \
+  --max-slides 10
+```
+
+## Apply Brand
+
+```bash
+# PowerPoint output
+python scripts/apply_brand.py synthesis.json \
+  --config assets/brand_config.json \
+  --output presentation.pptx
+
+# Preview HTML
+python scripts/apply_brand.py synthesis.json --preview
+```
+
+## Brand Configuration
+
+See `assets/brand_config.json` for:
+- Logo placement
+- Color scheme
+- Font settings
+- Slide templates
+
+## Output Formats
+
+- PowerPoint (.pptx)
+- Figma (via API)
+- HTML preview