AbstractRuntime v0.4.21

Added

• Public model-residency capability discovery on the AbstractCore host facade so hosts can branch on task support before showing warmup controls.
• Durable run-facade support for image edits through edit_image(...).
• First-class VisualFlow lowering for edit_image / image_to_image and generate_music media nodes.
• A focused troubleshooting guide and repository code of conduct in the core documentation set.

Changed

• Minimum optional AbstractCore dependency floor is now abstractcore>=2.13.25, matching the released Core validation for task-aware text/image/TTS/STT residency.
• Remote Runtime media execution now routes image edits through AbstractCore Server /v1/images/edits or provider-scoped /{provider}/v1/images/edits.
• Runtime no longer auto-derives session prompt-cache keys for non-text generated-media or transcription output selectors; explicit prompt_cache_binding remains supported.
• Local and remote model-residency responses now fail closed unless Core-owned residency truth verifies the loaded state.
• Runtime docs, backlog, ADR links, and AI-readable llms.txt / llms-full.txt now reflect the Core-owned residency boundary and current media node support.

Fixed

• Artifact-backed media resolution now preserves image/audio role metadata without failing when content type metadata is absent.