Feature / Add required class to inputs that are required

[Dacello]

Description

• Adds a class to input stacks that have a required input option. This is necessary to add custom styles (e.g. asterisk pseudo element to the label) of a required input
• Downgrades the phoenix liveview dependency to 16 because that is where heex was introduced and we are using this in an application which isnt at 17 yet. It shouldnt be required to be on liveview 17 to use the latest version of harmonium
• Minor version bump because this will cause breaking changes with projects that use https://github.com/revelrylabs/adminable, which currently also requires liveview 17+. I have a PR for adminable that will make a similar downgrade to liveview w/ minor version bump

[Dacello]

@stuartish i was also grumbling while I wrote it, but I didnt want to get into a rabbit hole of updating other places

[stuartish]

Human history shows that doing something the "right way" when everyone around you is doing it wrong has the primary effect of getting you killed so 👍