Makefile: Split run into new prebuild and run-only targets (#4450)

This provides a simple interface for build scripts that want to pre-run
the webpack and ts-compile steps (e.g. when producing a container
image) ahead of time rather, without requiring them to copy the current
set of commands needed for each part and hope they don't change.

Fixes #3287

Makefile

@@ -70,12 +70,20 @@ pre-commit: $(NODE_MODULES) test-min lint
 clean:  ## Cleans up everything
 	rm -rf node_modules .*-updated .*-bin out
 
-.PHONY: run
-run: prereqs  ## Runs the site like it runs in production
+.PHONY: prebuild
+prebuild: prereqs
 	$(NPM) run webpack
 	$(NPM) run ts-compile
+
+.PHONY: run-only
+run-only: node-installed  ## Runs the site like it runs in production without building it
 	env NODE_ENV=production $(NODE) $(NODE_ARGS) -r esm ./out/dist/app.js --webpackContent ./out/webpack/static $(EXTRA_ARGS)
 
+.PHONY: run
+run:  ## Runs the site like it runs in production
+	$(MAKE) prebuild
+	$(MAKE) run-only
+
 .PHONY: dev
 dev: prereqs ## Runs the site as a developer; including live reload support and installation of git hooks
 	./node_modules/.bin/supervisor -w app.js,lib,etc/config,static/tsconfig.json -e 'js|ts|node|properties|yaml' -n exit --exec $(NODE) $(NODE_ARGS) -- -r esm -r ts-node/register ./app.js $(EXTRA_ARGS)