feat: migrate to glam whenever relevant + migrate testbed to kiss3d instead of bevy + release v0.32.0 (#909)

* feat: migrate to glam whenever relevant + migrate testbed to kiss3d instead of bevy

* chore: update changelog

* Fix warnings and tests

* Release v0.32.0

src_testbed/testbed/mod.rs

@@ -0,0 +1,35 @@
+//! Testbed module - visual debugging and example runner for Rapier physics.
+
+#![allow(clippy::bad_bit_mask)]
+#![allow(clippy::unnecessary_cast)]
+#![allow(clippy::module_inception)]
+
+mod app;
+mod graphics_context;
+mod hover;
+mod keys;
+mod state;
+mod testbed;
+
+#[cfg(all(feature = "dim3", feature = "other-backends"))]
+use crate::physx_backend::PhysxWorld;
+
+// Re-export all public types
+pub use app::TestbedApp;
+pub use graphics_context::TestbedGraphics;
+pub use keys::KeysState;
+pub use state::{RunMode, TestbedActionFlags, TestbedState, TestbedStateFlags, UiTab};
+pub use testbed::{Example, Testbed};
+
+// Internal re-exports for other modules
+pub(crate) use state::{PHYSX_BACKEND_PATCH_FRICTION, PHYSX_BACKEND_TWO_FRICTION_DIR};
+
+/// Backend implementations for other physics engines
+#[cfg(feature = "other-backends")]
+pub struct OtherBackends {
+    #[cfg(feature = "dim3")]
+    pub physx: Option<PhysxWorld>,
+}
+
+/// Container for testbed plugins
+pub struct Plugins(pub Vec<Box<dyn crate::plugin::TestbedPlugin>>);