Malte Langkabel
c479291c1b
Revert of "Undo build button grid icons" (614dda8): restore the per-building
SVG icons, the QtSvg-based icon loading in BuildButtonGrid, the icon dir
plumbing in MainWindow, and the Qt5::Svg dependency.
This returns the unlock-groups branch to having the icons. The preceding
undo commit exists only so the Demolish -> Deconstruct rename can be
cherry-picked on its own (rename+icons commit together with the undo).
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Y7N59FsLA5e2kuVdqe4Uhc