[Fix] (MG_Backend/DirectVulkan): support Voxy rendering

Implemented:

- Advertise Voxy-required DirectVulkan extensions without raising the reported OpenGL version.

- Add DirectVulkan compute, indirect draw count, DSA, readback, and buffer state paths needed by Voxy.

Fixed:

- Enable Vulkan shaderInt64 and drawIndirectFirstInstance so Voxy baseInstance-driven LOD draws address the correct section data.

- Fix DirectVulkan synchronization, framebuffer, texture readback, and shader interface handling used by Voxy and Minecraft screenshots.

Tests:

- Add MG_Test coverage for DirectVulkan extension advertising, DSA buffer/texture/framebuffer/vertex-array behavior, persistent mapped readback, and shader/program paths.

MobileGL/MG_Backend/DirectVulkan/Renderer/VkBufferManager.cpp

@@ -67,7 +67,7 @@ namespace MobileGL::MG_Backend::DirectVulkan {
             .allocator = m_initInfo.allocator,
             .frameCount = m_initInfo.frameCount,
             .usage = VK_BUFFER_USAGE_VERTEX_BUFFER_BIT | VK_BUFFER_USAGE_INDEX_BUFFER_BIT |
-                     VK_BUFFER_USAGE_UNIFORM_BUFFER_BIT,
+                     VK_BUFFER_USAGE_UNIFORM_BUFFER_BIT | VK_BUFFER_USAGE_INDIRECT_BUFFER_BIT,
             .memoryUsage = m_initInfo.transientMemoryUsage,
             .allocationFlags = m_initInfo.transientAllocationFlags,
             .minBufferSize = m_initInfo.minUploadBytes,
@@ -201,7 +201,9 @@ namespace MobileGL::MG_Backend::DirectVulkan {
         case BufferKind::TextureBuffer:
             return VK_BUFFER_USAGE_UNIFORM_TEXEL_BUFFER_BIT;
         case BufferKind::ShaderStorage:
-            return VK_BUFFER_USAGE_STORAGE_BUFFER_BIT;
+            return VK_BUFFER_USAGE_STORAGE_BUFFER_BIT | VK_BUFFER_USAGE_INDIRECT_BUFFER_BIT;
+        case BufferKind::Indirect:
+            return VK_BUFFER_USAGE_INDIRECT_BUFFER_BIT | VK_BUFFER_USAGE_STORAGE_BUFFER_BIT;
         default:
             return 0;
         }