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/09-ourdigital-backoffice/code/SKILL.md

@@ -0,0 +1,167 @@
+---
+name: ourdigital-backoffice
+description: |
+  Business document creation for OurDigital consulting services.
+  Activated with "ourdigital" keyword.
+
+  Triggers:
+  - "ourdigital quote", "ourdigital 견적서"
+  - "ourdigital proposal", "ourdigital 제안서"
+
+  Features:
+  - Template-based document generation
+  - Cost calculation automation
+  - Document export
+version: "1.0"
+author: OurDigital
+environment: Code
+---
+
+# OurDigital Backoffice (Code)
+
+Automated business document generation with script support.
+
+## Activation
+
+Only with "ourdigital" keyword:
+- "ourdigital 견적서 [서비스]"
+- "ourdigital proposal [client]"
+
+## Quick Start
+
+```bash
+# Generate quote
+python code/scripts/generate_quote.py \
+  --client "ABC Company" \
+  --services "seo_audit,gtm_setup" \
+  --output quote.md
+
+# Create proposal
+python code/scripts/create_proposal.py \
+  --client "XYZ Corp" \
+  --project "마케팅 자동화" \
+  --duration "3months"
+
+# Cost analysis
+python code/scripts/cost_analysis.py \
+  --project "GTM 구축" \
+  --investment 5000000 \
+  --period 12months
+```
+
+## Scripts
+
+| Script | Purpose |
+|--------|---------|
+| `generate_quote.py` | Create quotes with pricing |
+| `create_proposal.py` | Build service proposals |
+| `cost_analysis.py` | ROI and cost-benefit |
+| `export_document.py` | Export to PDF/DOCX |
+
+## Quote Generation
+
+```bash
+# Single service
+python code/scripts/generate_quote.py \
+  --client "Client Name" \
+  --services "seo_audit" \
+  --output quote.md
+
+# Multiple services
+python code/scripts/generate_quote.py \
+  --client "Client Name" \
+  --services "seo_audit,gtm_setup,dashboard" \
+  --discount 10
+```
+
+## Service Codes
+
+| Code | Service | Base Price |
+|------|---------|------------|
+| `seo_audit` | SEO Technical Audit | 4,000,000 |
+| `seo_monthly` | SEO Monthly | 2,000,000/월 |
+| `gtm_setup` | GTM Setup | 3,000,000 |
+| `ga4_setup` | GA4 Implementation | 2,000,000 |
+| `dashboard` | Dashboard Dev | 4,000,000 |
+| `consulting` | Consulting Day | 1,500,000/일 |
+| `workshop` | Workshop | 1,500,000/회 |
+
+## Proposal Generation
+
+```bash
+# Standard proposal
+python code/scripts/create_proposal.py \
+  --client "XYZ Corp" \
+  --project "데이터 분석 환경 구축" \
+  --duration "2months" \
+  --services "gtm_setup,ga4_setup,dashboard"
+
+# With custom sections
+python code/scripts/create_proposal.py \
+  --client "ABC Company" \
+  --template custom \
+  --input requirements.json
+```
+
+## Cost Analysis
+
+```bash
+# ROI calculation
+python code/scripts/cost_analysis.py \
+  --project "마케팅 자동화" \
+  --investment 10000000 \
+  --annual_benefit 5000000 \
+  --period 36months
+
+# Comparison analysis
+python code/scripts/cost_analysis.py \
+  --compare "inhouse,outsource,hybrid" \
+  --period 12months
+```
+
+## Output Formats
+
+```bash
+# Markdown (default)
+python code/scripts/generate_quote.py --format markdown
+
+# PDF export
+python code/scripts/export_document.py \
+  --input quote.md \
+  --format pdf
+
+# Word export
+python code/scripts/export_document.py \
+  --input proposal.md \
+  --format docx
+```
+
+## File Structure
+
+```
+09-ourdigital-backoffice/
+├── code/
+│   ├── SKILL.md
+│   └── scripts/
+│       ├── generate_quote.py
+│       ├── create_proposal.py
+│       ├── cost_analysis.py
+│       └── export_document.py
+├── desktop/SKILL.md
+├── shared/
+│   ├── references/
+│   │   └── pricing-guide.md
+│   └── templates/
+│       ├── quote-template.md
+│       ├── proposal-template.md
+│       └── contract-template.md
+└── docs/CHANGELOG.md
+```
+
+## Quick Commands
+
+| Command | Action |
+|---------|--------|
+| "ourdigital 견적서 [서비스]" | Generate quote |
+| "ourdigital proposal [client]" | Create proposal |
+| "ourdigital 비용 분석 [project]" | Cost-benefit analysis |