Make sure to init fallback resources in bevy_sprite_render (#25574)

# Objective

- bevy_sprite_render is not adding the fallback resources which can
cause a crash when only 2d features are enabled.

## Solution

- Add init_fallback_resources to the RenderStartup of the
MaterialBindGroupPlugin so it's always initialized

## Testing

- I tested a separate empty project with only the 2d feature enabled and
it stopped crashing after this change

Closes #25572
Closes #25570

Author: IceSentry

crates/bevy_pbr/src/lib.rs

@@ -30,10 +30,7 @@ pub mod contact_shadows;
 #[cfg(feature = "bevy_gltf")]
 pub mod gltf;
 use bevy_light::cluster::GlobalClusterSettings;
-use bevy_render::{
-    material_bind_groups::init_fallback_resources, sync_component::SyncComponent,
-    view::RenderShadowLodOrigin,
-};
+use bevy_render::{sync_component::SyncComponent, view::RenderShadowLodOrigin};
 pub use contact_shadows::{
     ContactShadows, ContactShadowsBuffer, ContactShadowsPlugin, ContactShadowsUniform,
     ViewContactShadowsUniformOffset,
@@ -364,11 +361,7 @@ impl Plugin for PbrPlugin {
         render_app
             .add_systems(
                 RenderStartup,
-                (
-                    init_shadow_samplers,
-                    init_global_clusterable_object_meta,
-                    init_fallback_resources,
-                ),
+                (init_shadow_samplers, init_global_clusterable_object_meta),
             )
             .add_systems(
                 ExtractSchedule,

crates/bevy_render/src/material_bind_groups.rs

@@ -29,7 +29,7 @@ use crate::{
         OwnedBindingResource, PipelineCache, UnpreparedBindingResource, UnpreparedBindingResources,
     },
     storage::ShaderBuffer,
-    GpuResourceAppExt as _, Render, RenderApp, RenderSystems,
+    GpuResourceAppExt as _, Render, RenderApp, RenderStartup, RenderSystems,
 };
 use crate::{
     render_resource::{
@@ -536,6 +536,7 @@ impl Plugin for MaterialBindGroupPlugin {
             .allow_ambiguous_resource::<MaterialBindGroupAllocators>()
             .init_gpu_resource::<RenderMaterialBindings>()
             .allow_ambiguous_resource::<RenderMaterialBindings>()
+            .add_systems(RenderStartup, init_fallback_resources)
             .add_systems(
                 Render,
                 (
@@ -2328,7 +2329,7 @@ impl MaterialBindlessSlab {
 }
 
 /// Creates and inserts the [`FallbackBindlessResources`] and [`FallbackBuffer`].
-pub fn init_fallback_resources(mut commands: Commands, render_device: Res<RenderDevice>) {
+fn init_fallback_resources(mut commands: Commands, render_device: Res<RenderDevice>) {
     // Create the `FallbackBindlessResources`.
     commands.insert_resource(FallbackBindlessResources {
         filtering_sampler: render_device.create_sampler(&SamplerDescriptor {