Fix CI linker errors: Vulkan undefined symbols, WASM duplicate symbols

- Compile sc_backend_vulkan.h alongside test_gfx.c to provide Vulkan function definitions at link time
- Guard _IMPLEMENTATION defines in stock_dashboard.c with SC_NO_IMPLEMENTATION
- Set SC_NO_IMPLEMENTATION per-source property for stock_dashboard.c in WASM build, preventing symbol duplication with the unity TU

Author: amalxloop

.github/workflows/ci.yml

@@ -40,12 +40,14 @@ jobs:
             -Wall -Wextra -Wpedantic -Wshadow
       - name: Build and run Vulkan headless test
         run: |
-          clang -I include -I tools -DSC_GFX_IMPLEMENTATION \
+          clang -I include -I tools -I backends \
+            -DSC_GFX_IMPLEMENTATION \
             -DSC_GFX_BACKEND_VULKAN -DSC_BACKEND_VULKAN_IMPLEMENTATION \
             -DSC_LAYOUT_IMPLEMENTATION -DSC_WIDGET_IMPLEMENTATION \
             -DSC_RUNTIME_IMPLEMENTATION -DSC_FONT_IMPLEMENTATION \
             -Wall -Wextra -Wpedantic -Wshadow \
-            tests/test_gfx.c -lm -lvulkan -o /tmp/test_vk
+            -x c backends/sc_backend_vulkan.h tests/test_gfx.c \
+            -lm -lvulkan -o /tmp/test_vk
           /tmp/test_vk
 
   wasm:

apps/stock_dashboard/stock_dashboard.c

@@ -31,12 +31,14 @@
  *       stock_dashboard.c -o stock_dashboard -lm
  */
 
+#ifndef SC_NO_IMPLEMENTATION
 #define SC_GFX_IMPLEMENTATION
 #define SC_LAYOUT_IMPLEMENTATION
 #define SC_WIDGET_IMPLEMENTATION
 #define SC_RUNTIME_IMPLEMENTATION
 #define SC_FONT_IMPLEMENTATION
 #define SC_GFX_BACKEND_SOFTWARE
+#endif
 
 #include "../../include/sc_types.h"
 #include "../../include/sc_math.h"

tools/wasm/CMakeLists.wasm.cmake

@@ -96,6 +96,12 @@ target_include_directories(silvercore_wasm PRIVATE
     ${CMAKE_SOURCE_DIR}/tools
 )
 
+# stock_dashboard.c has its own _IMPLEMENTATION defines; suppress them
+# when compiling as part of the unity build to avoid duplicate symbols.
+set_source_files_properties(${CMAKE_SOURCE_DIR}/apps/stock_dashboard/stock_dashboard.c
+    PROPERTIES COMPILE_DEFINITIONS "SC_NO_IMPLEMENTATION"
+)
+
 set_target_properties(silvercore_wasm PROPERTIES
     OUTPUT_NAME "silvercore"
     SUFFIX ".js"