M5-01: Split IFC export modes

[DrunkOnJava]

Created from the roadmap audit in TODO.md.

Source: https://github.com/DrunkOnJava/rvt-rs/blob/main/TODO.md#L677
Tracking commit: 1ec8105

Scope

Labels: priority:P0, type:feature, area:ifc, area:cli

• Add explicit export modes:
  • scaffold
  • typed-no-geometry
  • geometry
  • strict
• Default user-facing CLI/viewer mode should warn when output is
  scaffold-only.

Acceptance criteria:

• rvt-ifc --mode strict fails if required real model data is missing.
• Viewer labels export quality before download.
• Python exposes the same mode option.

Definition of done

• The TODO acceptance criteria for this section are implemented or explicitly superseded by a linked decision.
• Tests, fixtures, or documentation are added at the level appropriate to the change risk.
• User-facing behavior and limitations remain honest in README/docs/viewer messaging.
• Relevant CI checks pass before the issue is closed.

[DrunkOnJava]

Implemented in a273ec2.

Summary:

• Added explicit IFC export quality modes: scaffold, typed-no-geometry, geometry, and strict.
• Added rvt-ifc --mode <mode>; strict/stronger modes validate diagnostics before writing IFC and fail loudly when required model data is missing.
• Kept requested diagnostics sidecars on failed strict exports so users can attach support evidence.
• Added default CLI warning when output is scaffold-only.
• Exposed the same quality-mode option in Python through RevitFile.write_ifc(mode=...) and rvt_to_ifc(path, mode=...).
• Updated the browser viewer to parse with diagnostics and show an export-quality label before downloads.
• Updated README/docs/status/Python/viewer docs and added regression tests.

Local validation:

• cargo test --test rvt_ifc_diagnostics_cli
• cargo test --test walker_to_ifc_integration --test rvt_ifc_diagnostics_cli
• cargo check --lib --features wasm --no-default-features
• cargo test -p rvt-py
• wasm-pack build --target web --out-dir viewer/pkg -- --features wasm --no-default-features
• npm run typecheck in viewer/
• npm run build in viewer/
• tools/quality.sh --quick

Note: the Python wheel built locally with maturin develop, but installing it into the venv was blocked by sandbox access to the uv cache, so I did not run pytest tests/python locally. The PyO3 crate compile and workspace quality gate passed.