This PR includes a new parameter in Addon:transform function to allow collect directives in injectionUsage metadata.

Right now there is no way to know what directives were used and so we cannot collect the info: we cannot use getImports since it can contains imports from other ids.

This PR is about the pending task here: nuxt/devtools#740 (comment)

/cc @antfu

Can this be done with injectImportsResolved ? If so, I will change this PR to add it to the vue-directives addon.
The problem is Nuxt where we have 2 unimport contexts: imports and directives (we only reuse some configuration from Nuxt imports options). We need to collect the imports from directives context and update them in the imports context.
Another problem is about custom directives injection, since there is no auto import, it is just a transform.