Add `cargo test --quiet` to the pre-push Rust block (sharing clippy's
target/ guard) so the suite runs automatically on every push touching
server/. Nothing ran the tests before — pre-push did only fmt/clippy/deny
and there is no CI — so a Rust regression could reach main unverified.
Document the resulting agent-spawn rule in team-patterns.md: don't have
implementation agents pre-run fmt/clippy/test pre-emptively, since the push
gate now enforces all three. The gate is authoritative; the lead patches any
fallout at push.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>