v1.0.4 of restage_codegen

A build_runner code generator that compiles Flutter-authored UI into Remote Flutter Widget (RFW) blobs and catalogs consumed by the Restage SDK runtime. Changelog excerpt: - Carry each component's full data schema in the standalone A2UI catalog document, not only the component discriminator, so a consumer reading the document alone (without the generated Dart) sees every component's fields and can generate rich payloads against it. - Suppress unused_elementin the generated A2UI catalog so a catalog that references only some of the shared helpers analyzes clean in the consumer's project.