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/04-ourdigital-research/code/SKILL.md

@@ -0,0 +1,124 @@
+---
+name: ourdigital-research
+description: |
+  Deep research and prompt generation for OurDigital.
+  Activated with "ourdigital" keyword.
+
+  Triggers:
+  - "ourdigital research", "ourdigital 리서치"
+  - "ourdigital deep research"
+
+  Features:
+  - Research planning
+  - Multi-source research
+  - Notion archiving
+  - Blog pipeline
+version: "1.0"
+author: OurDigital
+environment: Code
+---
+
+# OurDigital Research (Code)
+
+Research-to-publication workflow with script automation.
+
+## Activation
+
+Only with "ourdigital" keyword:
+- "ourdigital research [topic]"
+- "ourdigital 리서치"
+
+## Quick Start
+
+```bash
+# Export research to Ulysses
+python shared/scripts/export_to_ulysses.py --input research.md
+
+# Full pipeline
+python shared/scripts/research_pipeline.py --topic "AI Marketing" --output blog
+```
+
+## Workflow
+
+```
+Discovery → Planning → Research → Paper → Notion → Blog → Export
+```
+
+### 1. Discovery
+
+Ask clarifying questions:
+- Target audience?
+- Depth level?
+- Specific angles?
+
+### 2. Research Planning
+
+Generate:
+- Primary questions (3-5)
+- Secondary questions
+- Source strategy
+
+### 3. Deep Research
+
+Execute with tools:
+- `web_search` / `web_fetch`
+- `Notion:notion-search`
+- Internal documents
+
+### 4. Research Paper
+
+Synthesize into:
+```
+├── Executive Summary
+├── Key Findings
+├── Analysis
+├── Recommendations
+└── References
+```
+
+### 5. Notion Save
+
+Archive to Working with AI:
+- Database: f8f19ede-32bd-43ac-9f60-0651f6f40afe
+- Properties: Name, Status, AI used, Summary
+
+### 6. Blog Draft
+
+Route to appropriate skill:
+- Korean → `02-ourdigital-blog`
+- English → `03-ourdigital-journal`
+
+### 7. Export
+
+```bash
+python shared/scripts/export_to_ulysses.py --input draft.md
+```
+
+## Scripts
+
+| Script | Purpose |
+|--------|---------|
+| `export_to_ulysses.py` | Export to Ulysses app |
+| `research_pipeline.py` | Full automation |
+
+## Quick Commands
+
+| Command | Action |
+|---------|--------|
+| "ourdigital research [topic]" | Start discovery |
+| "ourdigital research → blog" | Full pipeline |
+| "ourdigital research → notion" | Research + save |
+
+## File Structure
+
+```
+04-ourdigital-research/
+├── code/SKILL.md
+├── desktop/SKILL.md
+├── shared/
+│   ├── references/
+│   │   └── research-frameworks.md
+│   └── scripts/
+│       └── export_to_ulysses.py
+└── docs/CHANGELOG.md
+```