make check: include blogex in the cheap static gate

Root check now loops app then blogex then the pin check, mirroring the shape
the Lens pass will use. blogex gains a check target (compile with warnings
fatal + format); credo is a marked slot until its dep exists, and the gate
never claims a sensor it did not run.

blogex/Makefile

@@ -3,13 +3,33 @@
 MISE_BIN ?= mise
 MISE_EXEC = $(MISE_BIN) exec --
 
-.PHONY: deps test format
+.PHONY: check precommit deps compile test format
 
+# Cheap static gate for this library (no database, no coverage). Runs from the
+# root `make check`, which loops app then blogex.
+#
+# Sensor slot: add `credo` once the "credo strict, tuned config (both apps)"
+# yak lands blogex's credo dep + .credo.exs. Do not list it before then — a
+# gate that claims a check it did not run is worse than no gate.
+check: compile format
+
+# Per-app precommit loop: same target name and alias shape as app/, so both
+# apps share one habit (compile --warning-as-errors, format, test).
+precommit:
+	$(MISE_EXEC) mix precommit
+
+# Sync dependencies
 deps:
 	$(MISE_EXEC) mix deps.get
 
+# Compile the project (warnings are fatal)
+compile:
+	$(MISE_EXEC) mix compile --warnings-as-errors
+
+# Run the test suite
 test: deps
 	$(MISE_EXEC) mix test
 
+# Format code
 format:
-	$(MISE_EXEC) mix format
+	$(MISE_EXEC) mix format