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, 16 insertions, 7 deletions

diff --git a/src/gpu/gpu.cc b/src/gpu/gpu.cc
index 63a30ff..fe71d3e 100644
--- a/src/gpu/gpu.cc
+++ b/src/gpu/gpu.cc
@@ -21,12 +21,13 @@
 
 static WGPUInstance g_instance = nullptr;
 static WGPUAdapter g_adapter = nullptr;
-WGPUDevice g_device = nullptr;  // Non-static for external access (debug builds)
-WGPUQueue g_queue = nullptr;    // Non-static for external access (debug builds)
+static WGPUDevice g_device = nullptr;
+static WGPUQueue g_queue = nullptr;
 static WGPUSurface g_surface = nullptr;
 static WGPUSurfaceConfiguration g_config = {};
-WGPUTextureFormat g_format = WGPUTextureFormat_BGRA8Unorm;  // Exposed for custom effects
+static WGPUTextureFormat g_format = WGPUTextureFormat_BGRA8Unorm;
 
+static GpuContext g_gpu_context = {};
 static MainSequence g_main_sequence;
 
 // --- Helper Functions ---
@@ -355,7 +356,12 @@ void gpu_init(PlatformState* platform_state) {
 
   g_config.device = g_device;
   g_config.format = swap_chain_format;
-  g_format = swap_chain_format;  // Update global format for external access
+  g_format = swap_chain_format;
+
+  // Update GPU context for accessor
+  g_gpu_context.device = g_device;
+  g_gpu_context.queue = g_queue;
+  g_gpu_context.format = g_format;
   g_config.usage = WGPUTextureUsage_RenderAttachment;
   g_config.width = platform_state->width;
   g_config.height = platform_state->height;
@@ -365,10 +371,9 @@ void gpu_init(PlatformState* platform_state) {
 
   InitShaderComposer();
 
-  g_main_sequence.init(g_device, g_queue, g_config.format,
-                       platform_state->width, platform_state->height);
+  g_main_sequence.init(g_gpu_context, platform_state->width, platform_state->height);
 
-  LoadTimeline(g_main_sequence, g_device, g_queue, g_config.format);
+  LoadTimeline(g_main_sequence, g_gpu_context);
 }
 
 void gpu_draw(float audio_peak, float aspect_ratio, float time, float beat) {
@@ -395,6 +400,10 @@ void gpu_add_custom_effect(Effect* effect, float start_time, float end_time, int
   seq->init(&g_main_sequence);
   g_main_sequence.add_sequence(seq, 0.0f, priority);
 }
+
+const GpuContext* gpu_get_context() {
+  return &g_gpu_context;
+}
 #endif /* !defined(STRIP_ALL) */
 
 void gpu_shutdown() {