Refactor Bevy_Picking to use MouseButton instead of PointerButton.

_release-content/migration-guides/pointer_button_to_mouse_button.md

@@ -0,0 +1,30 @@
+---
+title: PointerButton is now MouseButton.
+pull_requests: [25392]
+---
+
+Bevy picking used `PointerButton` for reasons...?
+This was limiting as it only exposed 3 buttons.
+It is also seemingly redundant, and now has been replaced with `MouseButton`.
+
+```rust
+PointerButton::Primary -> MouseButton::Left
+PointerButton::Middle -> MouseButton::Middle
+PointerButton::Secondary -> MouseButton::Right
+```
+
+Before:
+```rust
+MousePanSettings {
+    enabled: true,
+    button: PointerButton::Primary,
+}
+```
+
+After:
+```rust
+MousePanSettings {
+    enabled: true,
+    button: MouseButton::Left,
+}
+```

crates/bevy_camera_controller/src/pan_camera.rs

@@ -10,11 +10,11 @@ use bevy_camera::{Camera, RenderTarget};
 use bevy_ecs::prelude::*;
 use bevy_input::keyboard::KeyCode;
 use bevy_input::mouse::{AccumulatedMouseScroll, MouseScrollPixelsPerLine};
+use bevy_input::prelude::MouseButton;
 use bevy_input::ButtonInput;
 use bevy_math::{Vec2, Vec3};
 use bevy_picking::{
     events::{PointerDrag, PointerDragEnd, PointerDragStart},
-    pointer::PointerButton,
 };
 use bevy_time::{Real, Time};
 use bevy_transform::components::GlobalTransform;
@@ -91,7 +91,7 @@ pub struct MousePanSettings {
     /// Whether the mouse panning is enabled.
     pub enabled: bool,
     /// The mouse button to use for panning.
-    pub button: PointerButton,
+    pub button: MouseButton,
 }
 
 #[derive(Clone, Eq, PartialEq)]
@@ -146,7 +146,7 @@ impl Default for PanCamera {
             key_rotate_cw: Some(KeyCode::KeyE),
             mouse_pan_settings: MousePanSettings {
                 enabled: true,
-                button: PointerButton::Primary,
+                button: MouseButton::Left,
             },
         }
     }

crates/bevy_feathers/src/controls/number_input.rs

@@ -29,7 +29,6 @@ use bevy_picking::{
         PointerCancel, PointerDrag, PointerDragEnd, PointerDragStart, PointerPress, PointerRelease,
     },
     hover::Hovered,
-    pointer::PointerButton,
     PickingSystems,
 };
 use bevy_platform::collections::HashMap;
@@ -1017,7 +1016,7 @@ fn scrubber_on_release(
 
         // Copy of logic from EditableText / text_input, but done on pointer up instead of down.
         if drag_state.max_distance <= DRAG_THRESHOLD_DISTANCE {
-            if release.button != PointerButton::Primary {
+            if release.button != MouseButton::Left {
                 return;
             }