[EPIC]: Implement Mesh Shader Tests

@manon-traverse is already working on this.

Since May 7, 2026.

This issue exists to keep track of work going on around implementing mesh shaders.
Mesh Shader support requires a mix of adding new features to the framework as well as modifying existing functionality.
The list below is not an exhaustive list, more items are added as they are found to be needed. However, it should create some insight as to what work has been done for this feature and what work is going to happen in the near future for mesh shader support.

Legend:

- [ ] Not started yet
- [ ] In progress 🏗️
- [ ] In review 👀
- [x] Finished (merged in main)

### Framework Modfications/Features
- [x] Pipeline creation
- [x] Abstract pipeline creation functions https://github.com/llvm/offload-test-suite/pull/1070
- [x] Create mesh shader pipeline with Mesh Shader and Pixel Shader https://github.com/llvm/offload-test-suite/pull/1175
- [x] Create mesh shader pipeline with Amplification Shader.
- [x] Mesh Shader support in .test files
- [x] Add robust validation for various pipeline types (compute vs traditional raster vs mesh shader raster). #1148
- [x] Rework dispatch parameters to be extendable to other pipeline types #1152 #1153 👀
- [x] Make vertex buffers optional in rasterization test (mesh shaders don't use vertex buffers) #1154 #1155 👀
- [x] Add all the enums and yaml parsing for Mesh Shaders https://github.com/llvm/offload-test-suite/issues/1161
- [x] Add dispatching mesh shader on abstract command buffer and command encoder.
- [x] Introduce a Render(Pass)CommandEncoder for recording rasterization commands https://github.com/llvm/offload-test-suite/issues/1160
- [x] Add a method for dispatching a mesh shader https://github.com/llvm/offload-test-suite/pull/1175
- [x] Support Mesh Shaders on all graphics APIs https://github.com/llvm/offload-test-suite/issues/1216

### Tests
- [x] Triangle from Vertex IDs Test https://github.com/llvm/offload-test-suite/issues/1161
- [ ] Triangle from buffer containing vertices
- [ ] Amplification Shader test 👀 https://github.com/llvm/offload-test-suite/pull/1243
- [ ] Line geometry from Vertex IDs 🏗️
- [ ] Point geometry from Vertex IDs