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/README.md

@@ -0,0 +1,85 @@
+# OurDigital Document
+
+Notion-to-presentation workflow for OurDigital branded deliverables.
+
+## Purpose
+
+Transform Notion research into:
+- PowerPoint presentations
+- Figma slide decks
+- Branded executive summaries
+- Meeting materials
+
+## Activation
+
+Only activates with "ourdigital" keyword:
+- "ourdigital document [Notion URL]"
+- "ourdigital 발표자료 만들어줘"
+- "ourdigital presentation from research"
+
+## Workflow
+
+```
+Research Collection → Content Synthesis → Presentation Planning
+         ↓                    ↓                    ↓
+    Notion API          Key Topics           Slide Structure
+         ↓                    ↓                    ↓
+Slide Generation → Brand Application → Export
+         ↓                    ↓              ↓
+    Content           OurDigital Style   PPTX/Figma
+```
+
+## Structure
+
+```
+05-ourdigital-document/
+├── code/
+│   ├── SKILL.md
+│   ├── scripts/
+│   │   ├── run_workflow.py
+│   │   ├── extract_notion.py
+│   │   ├── synthesize_content.py
+│   │   └── apply_brand.py
+│   └── assets/
+│       └── brand_config.json
+├── desktop/
+│   ├── SKILL.md
+│   └── skill.yaml
+├── shared/
+│   └── references/
+│       ├── slide-layouts.md
+│       └── agenda-templates.md
+├── docs/
+│   └── CHANGELOG.md
+└── README.md
+```
+
+## Presentation Types
+
+| Type | Slides | Use Case |
+|------|--------|----------|
+| Executive | 3-5 | Board meetings, briefs |
+| Research | 10-20 | Deep analysis, reviews |
+| Meeting | 5-10 | Syncs, project updates |
+| Workshop | 8-15 | Training, collaboration |
+
+## Integration
+
+Works with:
+- `04-ourdigital-research` - Research input
+- `01-ourdigital-brand-guide` - Brand styling
+- Notion databases
+- Figma API
+
+## Environment
+
+Requires `~/.env.ourdigital`:
+```
+NOTION_API_TOKEN=<token>
+FIGMA_ACCESS_TOKEN=<token>
+```
+
+## Version
+
+- Current: 1.1.0
+- Author: OurDigital