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, 7 insertions, 9 deletions

diff --git a/src/gpu/effect.h b/src/gpu/effect.h
index 0cc9de5..006ee6f 100644
--- a/src/gpu/effect.h
+++ b/src/gpu/effect.h
@@ -9,7 +9,7 @@ class PostProcessEffect;
 
 class Effect {
  public:
-  Effect(WGPUDevice device, WGPUQueue queue) : device_(device), queue_(queue) {
+  Effect(const GpuContext& ctx) : device_(ctx.device), queue_(ctx.queue), format_(ctx.format) {
   }
   virtual ~Effect() = default;
   virtual void init(MainSequence* demo) {
@@ -42,6 +42,7 @@ class Effect {
  protected:
   WGPUDevice device_;
   WGPUQueue queue_;
+  WGPUTextureFormat format_;
   GpuBuffer uniforms_;
   int width_ = 1280;
   int height_ = 720;
@@ -49,8 +50,8 @@ class Effect {
 
 class PostProcessEffect : public Effect {
  public:
-  PostProcessEffect(WGPUDevice device, WGPUQueue queue)
-      : Effect(device, queue) {
+  PostProcessEffect(const GpuContext& ctx)
+      : Effect(ctx) {
   }
   bool is_post_process() const override {
     return true;
@@ -103,13 +104,10 @@ class MainSequence {
  public:
   MainSequence();
   ~MainSequence();
-  WGPUDevice device;
-  WGPUQueue queue;
-  WGPUTextureFormat format;
+  GpuContext gpu_ctx;
 
-  void init(WGPUDevice device, WGPUQueue queue, WGPUTextureFormat format,
-            int width, int height);
-  void init_test(WGPUDevice device, WGPUQueue queue, WGPUTextureFormat format);
+  void init(const GpuContext& ctx, int width, int height);
+  void init_test(const GpuContext& ctx);
   void add_sequence(std::shared_ptr<Sequence> seq, float start_time,
                     int priority = 0);
   void render_frame(float global_time, float beat, float peak,