feat(render3d): HDR10 output, and DLSS that stays still

HDR output: an HDR10 swapchain (A2B10G10R10, ST 2084 over BT.2020) when the
setting asks and the display offers it, with HDR metadata. The tonemap's HDR10
variant keeps the SDR picture up to a 200-nit paper white and rolls highlights
on to 1000 nits; the overlay's converts the interface to the same white. The
screen and LDR images go 10-bit with it; screenshots refuse while it is on.
OpenGL and the Vulkan SDR frame are unchanged. The instance asks for
VK_EXT_swapchain_colorspace. HDR metadata only where the loader has
vkSetHdrMetadataEXT: Streamline's interposer does not, and calling the thunk
crashed the game the moment the swapchain came up HDR10. PC 4K monitor: HDR10,
validation 0. R3D_HDR overrides the setting.

DLSS:
- the vertical jitter offset flips with Streamline's image (rows from the top):
  unflipped, Quality resolved the ground into concentric rings;
- preset K in every mode: the default M put Performance at 18 ms a frame at 4K
  on an RTX 3070 Ti (33 fps against 41 with DLSS off; with K, 60);
- the camera is jittered only while this frame holds a token and the last
  evaluate worked.
R3D_DLSS_PRESET, R3D_CAM_LOG (the camera and DLSS state a frame) and
R3D_NOGRAIN for measuring.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

packages/ludic.render3d/gpu_vk_res.ludic

@@ -11,6 +11,7 @@
 # supported Vulkan image format, so they are stored with four and expanded on upload.
 function gvk_format(ifmt: int) -> int {
   if ifmt == GL_RGBA8 or ifmt == GL_RGB8 { return VK_FORMAT_R8G8B8A8_UNORM }
+  if ifmt == GL_RGB10_A2 { return VK_FORMAT_A2B10G10R10_UNORM_PACK32 }   # the HDR10 screen and LDR image
   if ifmt == GL_SRGB8_ALPHA8 or ifmt == GL_SRGB8 { return VK_FORMAT_R8G8B8A8_SRGB }
   if ifmt == GL_R8 { return VK_FORMAT_R8_UNORM }
   if ifmt == GL_RG8 { return VK_FORMAT_R8G8_UNORM }