Fixes https://github.com/denoland/deno/issues/26509.
Ended up being a `deno_graph` bug causing the error to surface. This PR
updates `deno_graph` to pick up the fix and reverts the temporary
workaround that skipped JSON exports.
This allows using npm deps of jsr deps without having to add them to the
root package.json.
Works by taking the package requirement and scanning the
`node_modules/.deno` directory for the best matching package, so it
relies on deno's node_modules structure.
Additionally to make the transition from package.json to deno.json
easier, Deno now:
1. Installs npm deps in a deno.json at the same time as installing npm
deps from a package.json.
2. Uses the alias in the import map for `node_modules/<alias>` for
better package.json compatiblity.
