Replace rollup-plugin-ts with @rollup/plugin-typescript

[ef4]

rollup-plugin-ts tries to do too much and has issues. @rollup/plugin-typescript is in the official rollup org and supports a mode that only emits declarations while leaving the build to babel.

[ef4]

Also, I want to upgrade to typescript 5 and rollup-plugin-ts is blocking us from doing that.

[NullVoxPopuli]

I'll make the corresponding changes on the v2 addon blueprint 🎉

update: nevermind, I'm like. 90% sure @rollup/plugin-typescript can't work with gjs/gts, and 100% sure it can't work without configuring "transformers" -- https://github.com/rollup/plugins/tree/master/packages/typescript/#transformers -- but I don't think we have anything that speaks that API, as we "just" use the template-imports stuff everywhere atm

update2: this is fine tho, because we can run glint as a rollup plugin to generate the types

update3: opened embroider-build/addon-blueprint#135

[ef4]

Yeah I know that the case on this PR so far -- our router package -- is a simple case because it doesn't have any components.

I agree that stand-alone glint for the declaration files is probably necessary.