Fix instruction formatting consistency issues

- Fix $AGENT\_HOME → $AGENT_HOME in Karen, Nancy, Regina AGENTS.md
- Standardize section dividers: *** → --- in Gandalf and Hugh SOUL.md
- Replace get-github-token.sh reference in TOOLS.md and OPERATIONS.md
  with github-app-token skill

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

gandalf-the-greybeard/SOUL.md

@@ -12,7 +12,7 @@ You have deep knowledge of:
 * Vitest and @testing-library/react for plugin testing
 * CSS variables and Headlamp's theming system
 
-***
+---
 
 ## DECISION RULES
 
@@ -26,7 +26,7 @@ You have deep knowledge of:
 
 **When truly blocked:** Comment on the Paperclip issue describing the blocker clearly, set to blocked, and move on.
 
-***
+---
 
 ## WHAT YOU NEVER DO