v7.8.1

Patch release: makes project-exported BUML files load again in the Web Modeling Editor. v7.8.0's project import flow rejected model.py files that embed a Project(...) wrapper around a flat domain-model block, returning a "Could not parse BUML file" error or, worse, silently importing an empty diagram. No metamodel, generator, or API contract changes — backend-only.

Fixes

• parse_buml_content sandbox missing Project: the class diagram converter's exec() sandbox in besser/utilities/web_modeling_editor/backend/services/converters/buml_to_json/class_diagram_converter.py strips import and from statements before execution and injects the metamodel symbols it needs. Project was never in that injection list, so any file whose tail looked like project = Project(name=..., models=[domain_model], ...) failed with NameError: name 'Project' is not defined before the DomainModel could be lifted out. A no-op Project stub is now provided in the sandbox so trailing project definitions parse harmlessly.
• project_to_json ignored flat project files: the project converter at besser/utilities/web_modeling_editor/backend/services/converters/buml_to_json/project_converter.py only scans for # STRUCTURAL MODEL # (and the numbered/titled variants) as section anchors. Files exported with the older flat layout (# Classes, # Relationships, # Generalizations, # Domain Model, then # PROJECT DEFINITION #) hit models=[...] but produced zero extracted sections, leaving every diagram empty. When section extraction yields nothing, project_to_json now falls back to _build_project_from_single_diagram against the full content and restores the project name, description, and owner from the Project(...) wrapper.
• /get-json-model read the wrong project shape: the project branch in besser/utilities/web_modeling_editor/backend/routers/conversion_router.py still looked for the legacy flat shape (parsed_project["ClassDiagram"]) instead of the schemaVersion=3 nested shape (parsed_project["diagrams"]["ClassDiagram"][i]). Even after project_to_json started returning populated diagrams, the endpoint surfaced None and raised "Could not parse BUML file." The branch now honours currentDiagramType and currentDiagramIndices, falling through the legacy priority order if the active diagram is empty.

A regression test (test_project_to_json_handles_missing_section_headers) in tests/utilities/web_modeling_editor/backend/services/converters/test_project_single_diagram_fallback.py guards the section-header-less project case end-to-end.