29b3bd222c
Add a semantic_context column to canvas_nodes (schema, sqlc queries, generated models, repository upserts) and thread SemanticContext through the domain node, API type, and mappers so CAD-derived context survives canvas saves. Treat agent text parts with textSource "cad-context" like settings: keep them for planning, memory, and image-generation prompts but exclude them from the persisted user-visible message copy. Add coverage for the CAD context visibility and mapper behavior. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>