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/dintel-shared/README.md

@@ -0,0 +1,32 @@
+# dintel-shared — D.intelligence Agent Corps Shared Environment
+
+Shared Python package and utilities used by all `dintel-` Claude Skills (agents 70-77, 88).
+
+## Setup
+
+```bash
+cd /Users/ourdigital/Projects/our-claude-skills/custom-skills/dintel-shared
+python3 -m venv .venv
+source .venv/bin/activate
+pip install -e ".[dev]"
+```
+
+## Package Structure
+
+```
+src/dintel/
+├── __init__.py      # Version
+├── brand.py         # Brand constants, colors, service architecture, prohibited words
+├── document.py      # DOCX generation with D.intelligence branding
+├── excel.py         # Excel/xlsx generation with branded styles
+└── notion.py        # Notion database IDs, status options, client mappings
+```
+
+## Usage
+
+```python
+from dintel.brand import BRAND_NAME, SERVICE_MODULES, COLOR_PRIMARY
+from dintel.document import create_branded_doc, save_doc
+from dintel.excel import create_branded_workbook, style_header_row
+from dintel.notion import DB_TASKS_DASHBOARD, CLIENT_DB_MAP
+```