feat: add D.intelligence Agent Corps (9 skills + shared infra)

Add 9 agent skills (#70-#77, #88) for D.intelligence business operations:
brand guardian, brand editor, doc secretary, quotation manager, service
architect, marketing manager, back office manager, account manager, and
skill update meta-agent. Includes shared Python package (dintel), reference
docs, document/quotation templates, service module CSVs, cross-device
installer, and comprehensive user guide.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

custom-skills/75-dintel-marketing-mgr/shared/content-calendar-template.md

@@ -0,0 +1,76 @@
+# D.intelligence Content Calendar Template
+
+> Marketing Manager (#75) | Content Planning & Tracking
+
+## Monthly Content Calendar
+
+### YYYY-MM: [Month Theme/Focus]
+
+| Week | Date | Type | Channel | Title/Topic | Category Tag | SEO Keywords | Status | Owner | Notes |
+|------|------|------|---------|-------------|-------------|-------------|--------|-------|-------|
+| W1 | MM-DD | Magazine D. | Blog | | [Category] | | IDEA | #75 | |
+| W1 | MM-DD | LinkedIn | Social | | - | | IDEA | #75 | |
+| W2 | MM-DD | Newsletter | Email | | - | | IDEA | #75 | |
+| W2 | MM-DD | Magazine D. | Blog | | [Category] | | IDEA | #75 | |
+| W3 | MM-DD | LinkedIn | Social | | - | | IDEA | #75 | |
+| W3 | MM-DD | Magazine D. | Blog | | [Category] | | IDEA | #75 | |
+| W4 | MM-DD | Newsletter | Email | | - | | IDEA | #75 | |
+| W4 | MM-DD | LinkedIn | Social | | - | | IDEA | #75 | |
+
+## Status Definitions
+
+| Status | Description |
+|--------|-------------|
+| IDEA | Topic identified, not yet drafted |
+| DRAFT | Content drafted by Marketing Mgr (#75) |
+| REVIEW | Under review by Brand Editor (#71) and/or Brand Guardian (#70) |
+| APPROVED | Andrew has approved for publishing |
+| PUBLISHED | Live on target channel |
+| ARCHIVED | Removed from active calendar |
+
+## Content Type Guidelines
+
+### Magazine D. (Blog)
+- **Cadence**: 2-3 articles per month
+- **URL**: dintelligence.co.kr/dintelligence-magazine/
+- **Category Tags**: [Google Analytics 4], [Meta ADs], [Mixpanel], [SEO], [Data Analytics], [Marketing Strategy], [Content Marketing]
+- **Tone**: ~다 간결 서술체
+
+### Newsletter
+- **Cadence**: 2x per month (bi-weekly)
+- **Format**: Key metrics + practical insights + Magazine D. highlights
+- **Tone**: 간결, 인사이트 중심
+
+### LinkedIn
+- **Cadence**: 2-3 posts per month
+- **Format**: Industry insight + practical application
+- **Tone**: 인사이트, 실무 중심
+
+### Service Pages
+- **Cadence**: As needed (new services, updates)
+- **URL**: dintelligence.co.kr sections
+- **Tone**: ~합니다 존칭 서술체
+
+### Training Promo
+- **Cadence**: Per training event schedule
+- **Format**: Workshop/training announcement and promotion
+- **Tone**: ~합니다/~세요 혼용
+
+## Approval Chain Reminder
+
+```
+Marketing Mgr (#75) drafts
+  → Brand Editor (#71) checks writing
+    → Brand Guardian (#70) reviews compliance
+      → Andrew approves
+        → WordPress publish
+```
+
+## Monthly Review Checklist
+
+- [ ] All planned content published on schedule
+- [ ] SEO keywords aligned with strategic keyword plan
+- [ ] Content mix balanced across types and channels
+- [ ] Internal links to service modules included
+- [ ] Analytics review: top-performing content from previous month
+- [ ] Next month topics identified and calendar drafted