fix(v2): enforce hardened M0 contracts

Makefile

@@ -1,13 +1,17 @@
 PYTHON ?= .venv/bin/python
-PIP ?= .venv/bin/pip
+BOOTSTRAP_PYTHON ?= python3
 NPM ?= npm
 
-.PHONY: install test-fast lint typecheck frontend-build check-v1-absent check
+.PHONY: setup install test-fast lint typecheck frontend-build check-v1-absent check
 
-install:
-	$(PIP) install -e 'backend[dev]'
+setup:
+	test -x $(PYTHON) || $(BOOTSTRAP_PYTHON) -m venv .venv
+	$(PYTHON) -m pip install --upgrade pip
+	$(PYTHON) -m pip install -e 'backend[dev]'
 	$(NPM) --prefix frontend ci
 
+install: setup
+
 test-fast:
 	$(PYTHON) -m pytest tests/unit tests/contract -q