Add Makefile with check, build, docker, hooks targets

Targets: test (vitest, with conditional verbose rerun pattern), lint
(eslint + prettier), fmt / fmt-check (prettier), check (test + lint +
fmt-check), build (tsc), dev (tsc --watch), clean, docker, hooks.

Uses GNU timeout when available to hard-cap make test at 30 seconds, per
repo policy. Falls through without a cap on systems where timeout is
absent.

Makefile

@@ -0,0 +1,41 @@
+.PHONY: test lint fmt fmt-check check build dev clean docker hooks
+
+# Use `timeout` (GNU coreutils) when available so `make test` is hard-capped.
+# On macOS without coreutils this is empty and the cap is skipped.
+TIMEOUT := $(shell command -v timeout 2>/dev/null || command -v gtimeout 2>/dev/null)
+
+YARN := yarn run
+
+test:
+	@$(TIMEOUT) $(if $(TIMEOUT),30s,) $(YARN) vitest run --reporter=dot || \
+		{ echo "--- Rerunning with verbose for details ---"; \
+		  $(YARN) vitest run --reporter=verbose; exit 1; }
+
+lint:
+	@$(YARN) eslint .
+	@$(YARN) prettier --check .
+
+fmt:
+	@$(YARN) prettier --write .
+
+fmt-check:
+	@$(YARN) prettier --check .
+
+check: test lint fmt-check
+
+build:
+	@$(YARN) tsc
+
+dev:
+	@$(YARN) tsc --watch
+
+clean:
+	@rm -rf dist coverage .vitest-cache *.tsbuildinfo
+
+docker:
+	docker build -t quack .
+
+hooks:
+	@printf '#!/bin/sh\nset -e\nmake check\n' > .git/hooks/pre-commit
+	@chmod +x .git/hooks/pre-commit
+	@echo "Installed pre-commit hook (runs make check)."