Line tool inference like Fusion: parallel or perpendicular to existing lines, on a line's extension and tangent to circles and arcs, shown with a dashed guide and the snap label; placing the point adds the constraint (the existing curve stays, the new line follows)

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01AS5Tn3xieewUSg3uxrMVdL

crates/ui-egui/src/lib.rs

@@ -20,6 +20,7 @@ pub mod dialogs_sheet;
 pub mod dim_view;
 pub mod gpu;
 pub mod icons;
+pub mod inference;
 #[cfg(test)]
 mod menu_tests;
 pub mod palette;