build: add commitlint for angular convention

[lavjeetrai]

Description

This PR integrates @commitlint/cli and @commitlint/config-conventional to enforce the Angular commit convention across the project.

As mentioned in the Contributing section of our README, all commits must follow this format. Adding this tooling automatically validates commit messages and PR titles, preventing badly formatted commits from merging into main.

[lavjeetrai]

@sponce your views on this ?

[sponce]

All fine to me. @EdwardMoyse any objection to merging this ?

[EdwardMoyse]

I'm a bit nervous that I' m going to get flagged the whole time. ;-)

But actually, does this work? I just tried locally

emoyse@umassmacbookprom1pro1 phoenix % yarn commitlint --from HEAD~1 --to HEAD --verbose

⧗   --- input ---
Just adding some test
✖   Please add rules to your `commitlint.config.js`

And probably we'd want something in .husky too?

[rx18-eng]

I checked this locally. Right now this PR only adds the two commitlint packages and lockfile changes.

There is no commitlint config, no package script, no .husky/commit-msg as @EdwardMoyse said and no CI/PR-title check that runs it. With just these changes, commitlint fails with Please add rules to your commitlint.config.js, even for build: add commitlint for angular convention.

So this does not currently enforce commit messages or PR titles. It needs the config and hook/CI wiring before it does what the description says.

[lavjeetrai]

@EdwardMoyse @rx18-eng I have puhsed the changes and would appreciate a re-review!