Loads package.json for msg commands (create project, create resource, etc.). Finds package.json from cwd, validates directories, and derives module info.
Directory to start from (e.g. process.cwd())
Optional
requireL10n: if true, directories.l10n must exist (default: false)
Package context with pkgPath, rootDir, pkg, i18nDir, l10nDir?, isEsm, useTypeScript
Error if package.json not found or required directories missing
Loads package.json for msg commands (create project, create resource, etc.). Finds package.json from cwd, validates directories, and derives module info.