Add privacy-safe CAD compatibility report export

[KiYouJyo]

Goal

After v0.3.10 still renders the real Xiangyuan drawing as outlines only, stop guessing display primitives and make the app export the structural compatibility evidence needed to identify skipped ObjectARX proxy commands.

Adds

• right-side CAD viewer action: Export CAD compatibility report
• privacy-safe JSON report generated from the loaded reader-independent CadDocument
• app/CadCore/adapter versions plus safe aggregate reader metadata
• groups custom entities only by structural class identity/vendor/representation
• aggregates proxy primitive kinds, translated/unsupported counts, raw proxy command signatures and unknown type IDs/counts
• automatically saves to Desktop/SpatialViewer Diagnostics (LocalAppData fallback) and copies the report path to the clipboard
• zh-CN / ja-JP / en-US localization

Privacy boundary

The exporter uses an explicit metadata allow-list. It does not serialize the source drawing filename/path, entity handles, target handles, layer names, coordinates, raw property values, colors, text content, raw DWG/DXF bytes, or complete entity metadata.

The new raw-command fields will populate when the app ships with the corresponding CadCore diagnostic release; the exporter remains compatible when those fields are absent.

[KiYouJyo]

Superseded by PR #52 and the published SpatialViewer v0.4.2 release. The compatibility-report exporter was ported onto the current v0.4.1 baseline, updated for CadCore v0.12.10, passed Windows CI, and shipped without reverting the Rhino 0.4.1 fixes.