Load implementation attachments in cratis render, and move to Screenplay 4.32 and Stage 4.17

[woksin]

Added

• cratis render reads the implementation files a model references (file ... on policies, validation, reducers and other code) from the model folder, or from a single .play file's folder, and gives their contents to the Screenplay compiler, so file-backed code is identified by content. (Supply file attachment contents to the semantic model in cratis render #184)
• A file the loader refuses (outside the model folder, a link, missing, too large or not text) is reported as PLAY0430–PLAY0434, even when compilation fails. (Supply file attachment contents to the semantic model in cratis render #184)

Changed

• cratis render passes the model's implementation requirements and resolved code to Stage, so a missing or changed body stops rendering with STAGE-ESM-020 and the loader's reason. (Supply file attachment contents to the semantic model in cratis render #184)
• The CLI now bundles Screenplay 4.32.0 and Stage 4.17.0, and cratis run defaults to the matching cratis/stage:4.17.0 image.
• The render and run reference recommends a dedicated folder for models with file attachments: a single-file cratis run mounts only the .play file.