Make check run merge-check.sh, so a developer's check and the gate cannot drift

make check listed its own steps, and its gofmt walked vendor/, failing on
third-party files no change could fix; the steps after it never ran. It now
raises the throwaway database and runs the script repo-check runs.
novox/hq issue 431.

Makefile

@@ -99,16 +99,22 @@ proxy-image:
 	@echo
 	@docker image inspect $(PROXY_IMAGE) --format 'built {{.RepoTags}}  {{.Size}} bytes'
 
-# The whole gate. Raises a database, runs everything against it, and takes it down again --
-# including when the tests fail, which is why the teardown is not conditional.
+# The whole check. Raises a database, runs the repository's own check against it -- merge-check.sh,
+# the very script `mesh/repo-check` runs -- and takes the database down again, including when the
+# check fails, which is why the teardown is not conditional and the script's exit status is the
+# target's.
 #
-# **Packages in parallel, under the race detector, each test on a bus of its own** (internal/testbus).
-# It was one package at a time against one shared bus, because the live tests assert, read and remove
-# the mesh's own objects by their fixed names, and two packages at once deleted what the other read; the
-# suite was red run as Go runs it and read as noise. A bus per test, of the release the mesh runs, made
-# it the same in any order. The timeout bounds a hang to a failure with a stack, never a stalled gate.
-check: fmt vet postgres
-	@go test -race -timeout 15m ./... ; status=$$? ; $(MAKE) postgres-stop ; exit $$status
+# **It calls the script rather than restating it** (novox/hq issue 431): this target used to list its
+# own steps, its formatting step walked vendor/ where the script's does not, and it failed on
+# third-party code no change could fix -- so a developer's check and the gate disagreed, and the steps
+# after formatting never ran through it. The script is the one list of steps; this target only gives it
+# a database (MESH_TEST_POSTGRES, exported above).
+#
+# **Packages in parallel, under the race detector, each test on a bus of its own** (internal/testbus),
+# as the script runs them: a bus per test, of the release the mesh runs, makes the suite the same in any
+# order, and the timeout bounds a hang to a failure with a stack, never a stalled gate.
+check: postgres
+	@sh merge-check.sh ; status=$$? ; $(MAKE) postgres-stop ; exit $$status
 
 # Without a database the store's tests skip rather than fail, so this is the honest subset and not
 # the gate.
@@ -118,8 +124,10 @@ test:
 vet:
 	go vet ./...
 
+# Quick steps for a developer, not part of `check`. The directories gofmt reads must be the ones
+# merge-check.sh lists, never `.`, which walks vendor/ (novox/hq issue 431).
 fmt:
-	@unformatted=$$(gofmt -l . 2>/dev/null) ; \
+	@unformatted=$$(gofmt -l cmd internal examples) ; \
 	if [ -n "$$unformatted" ] ; then echo "not gofmt'd:" ; echo "$$unformatted" ; exit 1 ; fi
 
 postgres: