[Bug]: bzlmod extension performance

[jbedard]

What happened?

The rules_js bzlmod npm extensions are slower then the repository rules today due to parsing and iterating over the lockfile+npmrc file content multiple times.

How to reproduce

Run any build using the bzlmod npm.npm_translate_lock API and a large lockfile.

Known issues/reasons:

• parsing the pnpm lock twice
• ✅ generating npm_import targets twice (https://github.com/aspect-build/rules_js/pull/1547)