feat: allow useImage() args to be any reactive value

[stavros-tsioulis]

Hello, Vue has a more flexible approach to managing reactivity on composables with MaybeRefOrGetter types. Previously, with string | Ref<string>, computed or simple getter variables would not be allowed as TypeScript values of useImage (even though they would work as typeof would fail the string check).

On the code side, this allows:

const imageUrl = computed(() => /* ... */)
const image = useImage(imageUrl)

const { imageUrl } = defineProps<{
  imageUrl: string
}>()

const image = useImage(() => imageUrl)

There's a little perf upgrade of packaging all watchable values into one computed instead of creating up to 3 refs!

Happy to address any concerns about it :)

[stavros-tsioulis]

This is a little out of topic for this PR, but I had to update canvas to version 3 so that I could install the dependencies on my M-series Mac. Turns out canvas@2 doesn't have an ARM binary, so it would 404 on npm install. Tests seemed to run and pass just fine, so it may be worth considering making a dep upgrade.

[lavrton]

Thanks. Released.