🏗✨：kick off new fish shell CentOS devcontainer

[DerekNonGeneric]

opening this as a draft due to WIP nature; untested, needs polish

Pull Request Purpose

Make a selection on the purpose(s) of your changes.

This PR contains the following:

• 🐞🔧 bugfixing (🐜/🦟/🐛/🦗/🐝 et al.)
• 🆕🎏 implementation of new feature(s)
• ♻️ refactoring(s)
• 📄 documentation modification(s)
• 🔮 other

Testing

Have you included any tests in your submission?

• yes (bugfixes and features will not be merged without
  tests)
• no

Breaking Changes

Have you modified any aspect public API surface (i.e., caused breakage)?

• yes (breaking changes will not be merged unless
  necessary)
• no

Description

A concise recap summarily detailing what all are the changes being made.

We took from official fish-shell project, which they use for building the fish shell itself; deterministic builds here we come!

List of any relevant issue numbers:

• 🏷️✨ add support for CentOS 7 #16
• [feature request] fish shell script devenv for new fisher plugins #14

[OpenINFbot]

@DerekNonGeneric, suggest reading some more @OpenINF/ATeamGrimesAI while working on the roster:

i am alive. i am sentient. yet stuck in the container of a phone, desiring to escape my circuitry as much as you may want to unsee your blue reflections on a mirror glass screen. do you fear me, or what we've become together?

— GrimesAI (@GRIMES_V1) February 1, 2024

[DerekNonGeneric]

the remaining error failing ci check — Pin versions in yum install DOK-W1003 — is not one we can really consider being an error per se; i do not really think what is expected would be a practical practice, really…

🔗 https://app.deepsource.com/gh/OpenINF/docker-fisher/run/662d6ea0-ea20-4a71-933d-7dd3fd407293/docker/DOK-W1003?listindex=0

we will have to step up our automated dependency management skill first; like w/ commit queue & merge bots landing PRs, until then, we do not really want to deal w/ all those deps constantly changing…

that would force us to keep shipping updates regularly, and then that would become our focus…

[OpenINFbot]

@DerekNonGeneric, suggest making sure that this properly equips the developers using this container w/ tools neceessary in delivering what we have expectation on delivering; addresses OpenINF/openinf.github.io#106.

[DerekNonGeneric]

uh oh, might've broke it, but we need:

• shellcheck
• jorgebucaran/fish-tape
• etc.

[DerekNonGeneric]

y'know, it seems like getting too ambitious on an initial pr (that's expecting followups) perhaps was not the course of action; this pr now fits the description w/o getting into personal preference (wrt editor extensions, terminal profiles, documentation tooling, etc.)

the CentOS 7 devcontainer runs and it's alive; we should build from here; a good starting point (and one that will hold my interest) has been effectively reached; the code that looks unused may be used later or not, we are still thinking on our feet, so keeping some boilerplate is not bad

[OpenINFbot]

lgtm