docs(changes): changesets for DLSS and Reflex, HDR output, mesh-shader grass, the Vulkan grass fix and app native

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

changes/mesh-grass.md

@@ -0,0 +1,9 @@
+bump: minor
+type: feat
+**Mesh-shader grass** — on a card with `VK_EXT_mesh_shader`, `r3d_mesh_grass(on)` draws each chunk of grass
+tiles as one mesh-shader dispatch, and a blade that is culled emits no vertices at all.
+
+- **`ludic-dev shaders`** — a variant whose first file is `*.mesh` compiles that stage as a Vulkan 1.3 mesh
+  shader; its SPIR-V keeps the `.vert` name, so the manifest is unchanged.
+- **The seam** — `gpu_has_mesh()` and `gpu_draw_mesh_tasks(x, y, z)`; a mesh program's pipeline has no
+  vertex input and its bindings the mesh stage. The device enables `meshShader` and `maintenance4`.