tools: Migrate remaining tools to gobin

Replace ./scripts/install_tool.sh with `gobin`, such that we have
consistent handling for all tools needed for build and consistent
versioning within ./tools/mod/go.mod.

Side changes:
  - Expose /scripts/fix.sh that fixes formatting and bom across modules
  - Expose *.sh variants of scripts like build and ./test (first step
towards replacement).
  - Make stderr output of commands explicit and make commands use
different color than callouts.

build.sh

@@ -0,0 +1 @@
+build