refactor: reorganize skill numbering, remove obsolete skills, rename shared libs

- Rename: 00→80 claude-settings-optimizer, 88→79 dintel-skill-update,
  92→81 mac-optimizer, 93→82 tui-design-template
- Rename: dintel-shared → _dintel-shared (consistent with _ourdigital-shared)
- Remove: 61-gtm-manager, 62-gtm-guardian (obsolete), 99_archive
- Update all dintel-* skill refs (114 occurrences across 31 files)
- Sync README.md, CLAUDE.md, AGENTS.md with new structure

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

custom-skills/79-dintel-skill-update/shared/change-log.md

@@ -0,0 +1,32 @@
+# D.intelligence Agent Corps — Change Log
+
+> Changes to shared references propagated across dintel- skills by Agent #88.
+
+---
+
+## Format
+
+```yaml
+- date: YYYY-MM-DD
+  type: pricing | brand-guide | service-module | notion-schema | client-code | terminology
+  description: "Brief description of change"
+  source_files:
+    - _dintel-shared/src/dintel/brand.py
+  affected_skills:
+    - "#73 — updated pricing table"
+    - "#74 — updated module decision tree"
+  approved_by: Andrew
+```
+
+---
+
+## Log
+
+- date: 2026-03-08
+  type: initial-setup
+  description: "D.intelligence Agent Corps created — 8 agents (#70-#77) + meta-agent (#88)"
+  source_files:
+    - _dintel-shared/ (all files)
+  affected_skills:
+    - "All skills — initial creation"
+  approved_by: Andrew