v0.5.2

• Add NPM.PackageResolver — Node.js module resolution algorithm (specifier parsing, node_modules traversal, package.json entry points, extension probing)
• Fix ETS race condition in NPM.Resolver cache initialization
• Fix NPM.Cache.ensure/5 spec and docs to include {:ok, :missing_optional} return
• Fix dead code in NPM.PeerDeps version matching (redundant boolean case)
• Fix NPM.FileSize.by_extension/1 dead || branch (Path.extname never returns nil)
• Fix NPM.DepSort.install_order/1 dead {:error, :cycle} branch
• Fix crash in NPM.Linker nested version resolution on unparseable versions
• Replace blanket rescue _ with specific exception types across the codebase
• Flatten nesting in expand_all_optional_deps, solver_dependencies, select_group
• Bump ex_dna ~> 1.1 → ~> 1.3