feat: add model:opus to critical reasoning agents

- projman/planner.md - architecture decisions
- projman/code-reviewer.md - quality review
- pr-review/security-reviewer.md - security analysis
- code-sentinel/security-reviewer.md - security scanning
- data-platform/data-analysis.md - complex data insights

Fixes #303

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

plugins/code-sentinel/agents/security-reviewer.md

@@ -1,5 +1,7 @@
 ---
+name: security-reviewer
 description: Security-focused code review agent
+model: opus
 ---
 
 # Security Reviewer Agent