v20260412

Windows hotfix release for April 12, 2026.

What changed:

• Fixed a startup crash in the frozen GUI package.
• Root cause was recursive theme re-application during startup, which caused a stack overflow in the packaged app.
• The GUI still adapts to light/dark palettes, but theme updates are now guarded against re-entry.

Validation:

• python -m unittest discover -s tests
• Rebuilt Windows package via scripts\make_release.ps1
• Verified packaged GUI stays running after launch

Full Changelog: v20260411...v20260412