`spec_v2` migration tracking issue

# [`spec_v2`](https://github.com/bevyengine/bevy/pull/17373) migration tracking issue

This issue tracks the migration of bevy's rendering crates from the `SpecializedXPipeline` traits to those added the PR linked above.

[[Migration Guide](https://github.com/bevyengine/bevy/blob/main/release-content/migration-guides/composable_specialization.md)]

## High-level items

- [ ] Figure out patterns
- [ ] Bikeshed/review first migration PR, #19966
- [ ] Address structural comments in followup
- [ ] Migrate misc. specializer impls
- [ ] Migrate materials
- [ ] Deprecate (remove?) `SpecializedXPipeline`

## Per-crate checklist

### `bevy_core_pipeline`

- [ ] Auto Exposure #20125
- [ ] Blit #20117
- [ ] Bloom #19966
- [ ] Depth of Field
- [ ] Depth Downsampling
- [ ] Motion Blur
- [ ] Post Processing
- [ ] Skybox
- [ ] Tonemapping

### `bevy_anti_aliasing`

- [ ] Contrast Adaptive Sharpening
- [ ] FXAA
- [ ] SMAA
- [ ] TAA

### `bevy_gizmos`

- [ ] Line Gizmos

### `bevy_pbr`

- [ ] Atmospherics
- [ ] Deferred Lighting
- [ ] Prepass
- [ ] GPU Mesh Preprocessing
- [ ] Screen Space Ambient Occlusion
- [ ] Materials

### `bevy_sprite`

- [ ] Material 2D
- [ ] Sprite

### `bevy_ui_render`

- [ ] Box Shadow
- [ ] Gradient
- [ ] Node
- [ ] UI Material
- [ ] Texture Slice

### Examples

- [ ] `custom_gltf_vertex_attribute`
- [ ] `mesh2d_manual`
- [ ] `custom_shader_instancing`
- [ ] `shader_defs`
- [ ] `shader_material_wesl`
- [ ] `custom_vertex_attribute`
- [ ] `specialized_mesh_pipeline`
- [ ] `custom_render_phase`
- [ ] `lines`
- [ ] `manual_material`