Attaching an AmbientLight to a Camera causes unexpected warning message

## Bevy version

Bevy "0.16" via cargo

## \[Optional\] Relevant system information

cargo 1.86.0

Windows 11 Home 64 bit

AdapterInfo { name: "NVIDIA GeForce RTX 4070 SUPER", vendor: 4318, device: 10115, device_type: DiscreteGpu, driver: "NVIDIA", driver_info: "572.70", backend: Vulkan }

## What you did

Attached an `AmbientLight` component to an entity with a camera:

Cargo.toml
```
[package]
name = "ambient_light_issue"
version = "0.1.0"
edition = "2024"

[dependencies]
bevy = "0.16.0"
```

src/main.rs
```
use bevy::prelude::*;

fn main() {
App::new()
.add_plugins(DefaultPlugins)
.add_systems(Startup, setup_camera)
.run();
}

fn setup_camera(mut commands: Commands) {
commands.spawn((Camera2d, Camera { ..default() }, AmbientLight::NONE));
}
```

(also works without the explicit `Camera` component, or with a Camera3d, etc.)

## What went wrong

Warning:
WARN bevy_render::camera::camera: Entity 3v1 has a `Camera` component, but it doesn't have a render graph configured. Consider adding a `Camera2d` or `Camera3d` component, or manually adding a `CameraRenderGraph` component if you need a custom render graph.

## Additional information

Removing the `AmbientLight` component fixes it. printing a list of entities with Camera components during Update, does not print 3v1, and 3v1 is not the id of the spawned entity with the light and camera

Reproduce the warning with the minimal src/main.rs example, especially setup_camera and the Camera2d, Camera, and AmbientLight::NONE components. Trace the camera warning from the render-graph check and compare behavior when AmbientLight is removed. Done means the reported setup no longer emits the unexpected warning while valid camera configurations continue to warn appropriately.

Written by the indexing model from the issue text.