Linux app id: ai.storyteller.solidcraft, with an end-of-life rebase from the old id (#619)

The Flatpak app id, desktop/metainfo/MIME file names, icon name and the window's Wayland app_id / X11 class are now ai.storyteller.solidcraft, the id the ArtCraft launcher expects.

Existing Flatpak installs move over: the Pages repo marks app/ai.storyteller.solvecraft end-of-life with a rebase to the new id, so flatpak update offers the switch and Flatpak carries ~/.var/app along. A new install next to the old one copies settings and autosaves on first launch through a read-only grant on the old data folder. The metainfo declares <replaces>/<provides>, the desktop entry X-Flatpak-RenamedFrom, and AppImages drop the menu entry an older AppImage installed. deb/rpm upgrades remove the old-named files.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

packaging/linux/ai.storyteller.solidcraft.desktop

@@ -0,0 +1,16 @@
+[Desktop Entry]
+Type=Application
+Name=SolidCraft
+GenericName=3D CAD
+Comment=Parametric 3D CAD: sketch, constrain, extrude, and change a parameter to rebuild
+Exec=solidcraft %f
+TryExec=solidcraft
+Icon=ai.storyteller.solidcraft
+Terminal=false
+StartupNotify=true
+StartupWMClass=ai.storyteller.solidcraft
+Categories=Graphics;3DGraphics;Engineering;
+Keywords=cad;3d;parametric;sketch;step;stl;modelling;modeling;
+MimeType=application/x-solidcraft;model/step;model/iges;model/stl;model/3mf;
+# Releases before 0.8 used this desktop id; launchers keep pinned entries across the rename.
+X-Flatpak-RenamedFrom=ai.storyteller.solvecraft.desktop;