OccamForge v2.0.0

This release moves OccamForge from the v1 rule-based reduction workflow toward the v2 cost-based diagnostics and local edge-collapse path.

Highlights

Adds CollapseImpact diagnostics for simulated edge collapse after-change.
Splits CollapseImpact into independent metrics:
- normal_impact
- area_impact
- edge_length_impact
- removed_face_ratio
Uses normal_impact as the default GUI heatmap.
Keeps combined_experimental_impact hidden and marked experimental.
Adds a main-window Collapse Impact button for running the diagnostic directly.
Integrates CollapseImpact with the Heatmap Diagnostics flow before AFCost candidate generation.
Adds CLI entry points:
- occamforge-collapse-impact
- assetforge-collapse-impact