code-reviewing

Performs systematic code review with universal best practices and repo-specific standards. Auto-activates after significant code changes. Use when reviewing code, auditing files, checking PRs, examining staged changes, or when asked to "review", "check", "audit", or "examine" code. Enforces design principles (SOLID, DRY, KISS), security (OWASP), performance, concurrency safety, cross-platform compatibility, and codebase patterns.