Improve dev tooling

[aol-nnov]

• Add vscode recommended config and plugins
• Update docker machinery
• Simplify Makefile, eliminate the need of editing to enable CAPTURE for new tests. Now simply make (docker-)system-test CAPTURE=yes

Previously created docker stuff did not work (at
least in Dokcer Desktop for Mac). Let's try and
create something more generalzied. Yet, changes
were not tested on WSL.

[aol-nnov]

Code snippet

usermod -u `stat -c %u /work/src` aptly

mentioned in system/docker-wrapper did not work as expected on Docker Desktop for Mac (attached volume mount point is owned by root). Which leads to

$ make docker-image
[+] Building 310.3s (21/21) FINISHED
$ make docker-system-test
usermod: UID '0' already exists
make: *** [docker-system-test] Error 4
$ _

So, let's incorporate developer's UID and GID into image at build time.

N.B.: image is now "developer machine"-specific. Which is of no harm, I suppose, as it is only used for local development.