chore: rename H7CAD to Open CAD Studio

Joining the OpenAEC Foundation (open-aec.com). Crate/struct become
OpenCADStudio, user-facing strings use the spaced "Open CAD Studio"
form, repo URLs point to HakanSeven12/open-cad-studio. Logo (window
icon + assets/logo.svg) redrawn with OCS initials. Drop examples/
binaries — unused.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

src/scene/camera.rs

@@ -9,7 +9,7 @@
 // Zoom:      adjusts `distance` (exponential feel).
 // Snap:      directly assigns yaw+pitch encoded as a quaternion (for ViewCube).
 //
-// Coordinate convention: Z-up world space (same as the rest of H7CAD).
+// Coordinate convention: Z-up world space (same as the rest of OpenCADStudio).
 
 use glam::{vec3, Mat4, Quat, Vec3};
 use iced::{Point, Rectangle};