Parallel Agent Type Contracts

When launching parallel agents for code implementation, prevent type duplication.

Required in Every Agent Prompt

1. Verification Command (MANDATORY)

## Before Marking Complete
Run verification:
\`\`\`bash
npx tsc --noEmit 2>&1 | head -20
\`\`\`
If ANY type errors exist, fix them before completing.

2. Grep-Before-Create

## Before Creating Any Type/Interface