Restore trigger phrases as ## Usage Examples across 10 engineering skills

Renamed ## Example Trigger Phrases → ## Usage Examples to make the section
clearly human-facing documentation rather than a system instruction.
Restores content that was removed in the previous quality pass.

Skills updated (both skills/ and plugins/pm-engineering/skills/):
code-review-checklist, debugging-log-analyser, changelog-generator,
pr-description-writer, system-design-interview, test-strategy-doc,
runbook-writer, incident-postmortem, api-docs-writer,
architecture-decision-record

https://claude.ai/code/session_01C3HwChrccJd145vJ6Z7ajF

plugins/pm-engineering/skills/changelog-generator/SKILL.md

@@ -73,3 +73,10 @@ Follow [Keep a Changelog](https://keepachangelog.com) format:
 - [ ] Version and date header is correct
 - [ ] Empty sections are omitted
 - [ ] Tone is imperative mood throughout
+
+## Usage Examples
+- "Write a changelog for version [X]" + [paste commits]
+- "Generate release notes from these commits"
+- "Turn this git log into a CHANGELOG entry"
+- "Write the CHANGELOG.md update for this release"
+- "What changed in this release?" + [paste commit list]