graphics: checkpoint live Vulkan pipeline cache after new compilations

Co-authored-by: fxpw <fxpw@outlook.com>

src/graphics/host_gpu/renderer/pipeline/pipelineCache.h

@@ -8,6 +8,7 @@
 #include "graphics/host_gpu/vulkanCommon.h"
 #include "graphics/shader/shader.h"
 
+#include <chrono>
 #include <cstddef>
 #include <filesystem>
 #include <memory>
@@ -173,11 +174,14 @@ private:
 	std::unique_ptr<ProgramCache> m_program_cache;
 	vk::PipelineCache             m_driver_cache = nullptr;
 	std::filesystem::path         m_driver_cache_path;
+	std::chrono::steady_clock::time_point m_next_driver_cache_save;
+	bool                          m_driver_cache_dirty = false;
 	std::unordered_map<GraphicsPipelineKey, std::unique_ptr<Pipeline>, GraphicsPipelineKeyHash>
 	                                                        m_graphics_pipelines;
 	std::unordered_map<uint64_t, std::unique_ptr<Pipeline>> m_compute_pipelines;
 
 	void InitializeDriverCache();
+	void CheckpointDriverCache();
 };
 
 void LogPipelineTrace(const char* phase, uint64_t vertex_program_id, uint64_t pixel_program_id);