[WIP] feat: add frontend tooling

[millnut]

What does this change?

Fixes #183. This adds frontend tooling for Lando and DDEV for eslint and stylelint.

WIP: DDEV config to do

[finnlewis]

@millnut I'm just looking at adding the same commands to ddev

[millnut]

Great thanks @finnlewis could you commit to this branch I've got some more local changes to push to this as well

[tonypaulbarker]

@finnlewis @millnut I was looking at some of the localgov_base JS lint issues and thought helpful to share some feedback.

The readme references the localgov_base but that project has its own instructions in its readme https://github.com/localgovdrupal/localgov_base/blob/1.x/README.md .
I think linting should be run and fixed per contrib project since any changes need to be committed to the individual project, otherwise fixes applied to contrib projects can be overwritten by the next composer update.

Which files to lint (e.g. web/modules/contrib/localgov_base/**/*.css snippet) can be specified in a package.json e.g. line 9 of https://github.com/localgovdrupal/localgov_base/blob/1.x/package.json .

There may well be a place for scanning and making changes at this level (for installing core packages / for custom code / to scan for problems to create tasks).

The most important thing is that we have a consistent approach so everyone gets the same output.

I think it would be great if the readme could include some context about the use cases.