fix(skills): add Anti-Patterns sections, fix descriptions, quality checks, and required inputs

- Add Anti-Patterns section (3-5 binary checkboxes) to all modified skills
- Fix Quality Checks to use binary checkbox format where needed
- Rewrite descriptions to verb-when-produces format where needed
- Add Required Inputs sections to skills missing them
- Fix email-triage frontmatter YAML quoting

https://claude.ai/code/session_01MuGKn3a3Gbqoe8uM5Lmuqt

skills/executive-update/SKILL.md

@@ -58,3 +58,11 @@ Ask the user for these if not provided:
 - [ ] Every risk has a mitigation or watch action
 - [ ] Every decision needed has at least two options and a recommendation
 - [ ] Written for a CFO or CEO — no jargon, all outcomes
+
+## Anti-Patterns
+
+- [ ] Do not lead with context or background — executives read the headline first; bury the important thing below two sentences of setup and they will miss it
+- [ ] Do not present metrics without a comparison point — a number without context (vs. target, vs. last period) cannot be interpreted and will prompt follow-up questions
+- [ ] Do not soften or spin risks — executives rely on these updates to make resource and escalation decisions; sanitised risk sections destroy the update's utility
+- [ ] Do not present a "Decisions Needed" item without a recommendation — asking an executive to decide without your view forces them to do the analytical work the PM should have done
+- [ ] Do not exceed 250 words in the main body — length signals the author has not done the compression work; every word over 250 reduces the chance the update is read