vulkan : incremental shader builds (#16341)

* vulkan (DRAFT): split shader generation by GLSL source file, to improve incremental build times

* support dep-files so shaders are recompiled if their included files change

* rename shader files which are used as "headers" to use .glsl extension
* move glslc extension detection shaders to separate folders
* the above is to prevent them from getting glob'd with the actual compute shaders that need to be compiled

* vulkan : only write embedded shader .hpp/.cpp when they change

* avoid recompiling ggml-vulkan.cpp when editing shaders
* pass single --source argument instead of --input-dir & --filter to shader gen
* check for source file match earlier

* fix hang in vulkan-shaders-gen when there are compilation errors

* early out did not decrement compile_count

* clean up

* fix glslc integer dot product test

* unconditionally write the embedded shader cpp output

* replace output filepath in generated dep-files to match output in CMakeLists

---------

Co-authored-by: Jeff Bolz <jbolz@nvidia.com>

ggml/src/ggml-vulkan/vulkan-shaders/flash_attn_cm2.comp

@@ -16,9 +16,9 @@
 #extension GL_KHR_shader_subgroup_vote : enable
 #extension GL_EXT_null_initializer : enable
 
-#include "types.comp"
-#include "dequant_funcs_cm2.comp"
-#include "flash_attn_base.comp"
+#include "types.glsl"
+#include "dequant_funcs_cm2.glsl"
+#include "flash_attn_base.glsl"
 
 layout (binding = 0) readonly buffer Q {uint8_t data_q[];};
 layout (binding = 1) readonly buffer K {uint8_t data_k[];};