[legacy-framework] Add lint rule 'no-anonymous default export' for new apps

[Shinyaigeek]

Type: linting, feature, Docs

Closes: blitz-js/legacy-framework#507

What are the changes and their implications? ⚙️

• Adds rule no-anonymous-default-export to eslint config in templates
• Adds rule no-anonymous-default-export to eslint config in each examples
• fix: change default exported anonymous component in examples -> default exported Named component
• fix: change default exported anonymous component in USER_GUIDE.md -> default exported Named component
• fix: change default exported anonymous function in @blitz/server -> default exported Named function

Checklist

N/A

Breaking change: no

Other information

N/A

[flybayer]

Thank you @Shinyaigeek!! Looks good to me — we'll wait on @ryardley

@all-contributors add @Shinyaigeek for code

[allcontributors]

@flybayer

I've put up a pull request to add @Shinyaigeek! 🎉

[flybayer]

I guess one question is whether to have this as a warning or an error. I was initially thinking error.

[Shinyaigeek]

@flybayer
Sure, enforce means error rather than warn, sorry 🙏
I fixed this in 3e951a7