Enable injecting debug IDs into indexed sourcemaps #110
Description
The sourcemaps crate currently contains APIs to allow injecting debug IDs into non-indexed sourcemaps (represented using the SourceMap struct) from Sentry CLI.
However, indexed sourcemaps (represented usingSourceMapIndex ) are lacking API features that the CLI would need in order to inject them with debug IDs. To unblock CLI-60, we need to add these APIs.
The subissues will detail specifically what APIs we need to add.