refactor: Bundle GPU context into GpuContext struct

- Created GpuContext struct {device, queue, format}
- Updated Effect/PostProcessEffect to take const GpuContext&
- Updated all 19 effect implementations
- Updated MainSequence.init() and LoadTimeline() signatures
- Updated generated timeline files
- Updated all test files
- Added gpu_get_context() accessor and fixture.ctx() helper

Fixes test_mesh.cc compilation error from g_device/g_queue/g_format conflicts.
All targets build successfully.

1 files changed, 3 insertions, 4 deletions

diff --git a/src/gpu/effects/particle_spray_effect.cc b/src/gpu/effects/particle_spray_effect.cc
index e8ead0a..452017e 100644
--- a/src/gpu/effects/particle_spray_effect.cc
+++ b/src/gpu/effects/particle_spray_effect.cc
@@ -6,9 +6,8 @@
 #include <vector>
 
 // --- ParticleSprayEffect ---
-ParticleSprayEffect::ParticleSprayEffect(WGPUDevice device, WGPUQueue queue,
-                                         WGPUTextureFormat format)
-    : Effect(device, queue) {
+ParticleSprayEffect::ParticleSprayEffect(const GpuContext& ctx)
+    : Effect(ctx) {
   uniforms_ =
       gpu_create_buffer(device_, sizeof(float) * 6,
                         WGPUBufferUsage_Uniform | WGPUBufferUsage_CopyDst);
@@ -27,7 +26,7 @@ ParticleSprayEffect::ParticleSprayEffect(WGPUDevice device, WGPUQueue queue,
       {particles_buffer_, WGPUBufferBindingType_ReadOnlyStorage},
       {uniforms_, WGPUBufferBindingType_Uniform}};
   render_pass_ =
-      gpu_create_render_pass(device_, format, particle_render_wgsl, rb, 2);
+      gpu_create_render_pass(device_, format_, particle_render_wgsl, rb, 2);
   render_pass_.vertex_count = 6;
   render_pass_.instance_count = NUM_PARTICLES;
 }