Pre-commit hook runs lint+fmt-check, not full check (TDD)

Tests are deliberately excluded from the pre-commit hook so that the
TDD red-phase commit (failing tests landing before implementation) can
land on a feature branch. CI still runs full make check via docker build
so a red branch cannot reach main.

Makefile

@@ -36,6 +36,10 @@ docker:
 	docker build -t quack .
 
 hooks:
-	@printf '#!/bin/sh\nset -e\nmake check\n' > .git/hooks/pre-commit
+	@printf '#!/bin/sh\nset -e\nmake lint\nmake fmt-check\n' > .git/hooks/pre-commit
 	@chmod +x .git/hooks/pre-commit
-	@echo "Installed pre-commit hook (runs make check)."
+	@echo "Installed pre-commit hook (runs make lint && make fmt-check)."
+	@echo "Note: tests are deliberately not in the pre-commit hook so the"
+	@echo "TDD red-phase commit (failing tests, no implementation yet)"
+	@echo "can land. CI runs make check via docker build, which catches"
+	@echo "any branch that ships red."

README.md

@@ -90,6 +90,11 @@ All work on quack is test-driven. No exceptions.
    test-then-implementation sequence into reviewable commits, but the final
    history must still show tests landing before (or with) the matching
    implementation.
+8. The pre-commit hook installed by `make hooks` runs
+   `make lint && make fmt-check`, not the full `make check`. This is deliberate
+   so the TDD red-phase commit (failing tests, no implementation yet) can land.
+   The full `make check` runs as part of `docker build .`, which is what CI
+   executes, so a red branch still cannot reach `main`.
 
 ## Design