feat(codemods): add import alias and directory helpers

[RomainLanz]

Package configure scripts currently have to edit the application’s package.json and create directories themselves. Adding an import alias should not require the optional Assembler package.

Add addImportAlias(alias, target) and createDirectory(path) directly to core. Existing aliases and directories remain unchanged. Updating package.json preserves its indentation and line endings.

Tests: 23 codemod tests passed; lint, typecheck and build passed. The build still reports unresolved-import warnings in factories/core/ignitor.ts.

[thetutlage]

Yo, can you open a PR for the docs too? Maybe document here? https://docs.adonisjs.com/guides/concepts/scaffolding#codemods-api-reference

[RomainLanz]

Done!