build: improve Makefile command visibility and help format

Suppress the echo of internal shell commands by default to reduce
terminal noise during the build process. Maintain color-coded status
messages utilizing the MSG macro to provide clear section headers
and progress indicators.

Additionally, refactor the `make help` target to use a custom awk
formatter. This enforces a fixed
30-character width for target names
and highlights them in cyan, preventing description overlap and
improving overall readability.

Author: Euler-B