feat: add gravity and gravity-movement plugins

Add CHGravityPlugin to manage the global gravity resource and
CHGravityMovementGluePlugin to apply gravity to movement velocity
each fixed update. Update workspace dependencies and include the
new crates in the main app.

2 files changed, 38 insertions, 0 deletions

diff --git a/plugins/glues/gravity_movement/Cargo.toml b/plugins/glues/gravity_movement/Cargo.toml
new file mode 100644
index 0000000..4b5790c
--- /dev/null
+++ b/plugins/glues/gravity_movement/Cargo.toml
@@ -0,0 +1,9 @@
+[package]
+name = "ch-gravity-movement"
+version.workspace = true
+edition.workspace = true
+
+[dependencies]
+bevy.workspace = true
+ch-movement.workspace = true
+ch-gravity.workspace = true
diff --git a/plugins/glues/gravity_movement/src/lib.rs b/plugins/glues/gravity_movement/src/lib.rs
new file mode 100644
index 0000000..da31061
--- /dev/null
+++ b/plugins/glues/gravity_movement/src/lib.rs
@@ -0,0 +1,29 @@
+//! CH Glue - Gravity & Movement
+//!
+//! This module provides the glue layer for the Gravity and Movement modules.
+
+#![deny(missing_docs)]
+
+use bevy::{
+    app::{FixedUpdate, Plugin},
+    ecs::system::{Query, Res},
+};
+use ch_gravity::Gravity;
+use ch_movement::{Movement, Velocity};
+
+/// Cigarette Hacker gravity movement glue
+pub struct CHGravityMovementGluePlugin;
+
+impl Plugin for CHGravityMovementGluePlugin {
+    fn build(&self, app: &mut bevy::app::App) {
+        app.add_systems(FixedUpdate, apply_gravity_to_movement);
+    }
+}
+
+fn apply_gravity_to_movement(mut query: Query<(&mut Velocity, &Movement)>, gravity: Res<Gravity>) {
+    for (mut velocity, _movement) in query.iter_mut() {
+        velocity.x += gravity.x;
+        velocity.y += gravity.y;
+        velocity.z += gravity.z;
+    }
+}