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/08-ourdigital-trainer/README.md

@@ -0,0 +1,82 @@
+# OurDigital Trainer
+
+Training material creation and workshop planning for OurDigital education programs.
+
+## Purpose
+
+Design and deliver effective training:
+- Curriculum design for Data/AI literacy
+- Workshop agenda planning
+- Participant evaluation frameworks
+- Training material development
+
+## Activation
+
+Only activates with "ourdigital" keyword:
+- "ourdigital training on [topic]"
+- "ourdigital 워크샵 기획해줘"
+- "ourdigital curriculum for [subject]"
+
+## Core Domains
+
+| Domain | Topics |
+|--------|--------|
+| Data Literacy | 데이터 리터러시, 분석 기초, 시각화 |
+| AI Literacy | AI 활용, 프롬프트 엔지니어링, AI 윤리 |
+| Digital Marketing | SEO, GTM, 마케팅 자동화 |
+| Brand Marketing | 브랜드 전략, 콘텐츠 마케팅 |
+
+## Structure
+
+```
+08-ourdigital-trainer/
+├── code/
+│   ├── SKILL.md
+│   └── scripts/
+│       ├── generate_curriculum.py
+│       ├── create_workshop.py
+│       └── create_evaluation.py
+├── desktop/
+│   ├── SKILL.md
+│   └── skill.yaml
+├── shared/
+│   ├── references/
+│   │   ├── training-frameworks.md
+│   │   └── activity-library.md
+│   └── templates/
+│       └── workshop-template.md
+├── docs/
+│   └── CHANGELOG.md
+└── README.md
+```
+
+## Workshop Formats
+
+| Format | Duration | Best For |
+|--------|----------|----------|
+| Mini | 2 hours | Single topic intro |
+| Half-day | 4 hours | Comprehensive overview |
+| Full-day | 8 hours | Deep dive + practice |
+| Series | Multiple | Skill building program |
+
+## Evaluation Framework
+
+| Level | Measure | Method |
+|-------|---------|--------|
+| Reaction | Satisfaction | Survey |
+| Learning | Knowledge gain | Pre-post test |
+| Behavior | Application | Observation |
+| Results | Performance | KPI tracking |
+
+## Integration
+
+Works with:
+- `05-ourdigital-document` - Training slides
+- `06-ourdigital-designer` - Visual materials
+- `01-ourdigital-brand-guide` - Presentation style
+- Google Slides, Notion
+
+## Version
+
+- Current: 1.0.0
+- Author: OurDigital