Agent Persistence With Build and Typecheck Verification

Pair GPT-4.1 and Gemini 3's agentic persistence directives (keep going until the query is completely resolved and verified) with the build and type-check commands in AGENTS.md.

## Verification Protocol
Do not yield control back to the user until you have run both the single-file test command and the type-check command defined in ./AGENTS.md and confirmed zero errors.