engine: presets E/F AutoExposure, the game's exposure fields and NGX's jitter order

NGX's CNN takes this frame's exposure scale and pre-exposure in both translated kernels (input words 244-256,
reconstruction 592-604) and the previous frame's exposure as the input kernel's texture 352
(cuda_copy_exposure_kernel's half surface). The runtime left all of it at the model dump's values, so HDR games
with a pre-exposure other than 1 or a changing exposure measured 18-39 dB against NGX; now 54-64 dB.

AutoExposure (flag 0x40), which the shim refused for E/F: NGX runs K's log-mean measurement on M's grid every
second frame. exposure_k.comp MODE 3 writes it to the 1x1 image the kernels sample; sr/exposure_copy_e.comp
keeps the previous exposure. 60-66 dB over eleven frames at 960x540 -> 1920x1080, pre-exposure 19-21.

The reconstruction's jitter words 544-556 are (y, x); the runtime wrote (-x, -y), which matches only the
harness's first three jitters, so every later frame of a game's jitter sequence measured 26-28 dB. Twelve-frame
captures now measure 60-66 dB HDR and LDR; on the Steam Deck through the shim 51-67 dB against ZLUDA.

The D3D12 harness takes per-frame lists in D4R_HARNESS_PRE_EXPOSURE / _EXPOSURE_SCALE; d4r-e takes the
AutoExposure flag, per-frame exposure values and the game's exposure texture. E/F models need rebuilding
(the install's model cache key changes); older models keep the old binding and refuse AutoExposure.

engine/runtime.h

@@ -317,6 +317,7 @@ struct EFrameSettings {
     float jitter[2] = {0, 0};       // render pixels, as the game passes them to NGX
     float motionScale[2] = {1, 1};  // NGX's MV scale: motion texels times this are the motion's pixels
     bool reset = false;
+    float preExposure = 1, exposureScale = 1;   // the game's (DLSS.Pre.Exposure, DLSS.Exposure.Scale)
 };
 class EModel {
 public:
@@ -326,6 +327,7 @@ public:
     EModel& operator=(const EModel&) = delete;
     void recordUpload(VkCommandBuffer command);
     bool uploadRecorded() const;
+    bool hasAutoExposure() const;   // the model directory holds the exposure shaders (exposure_e0/1.spv)
 private:
     struct Impl;
     std::unique_ptr<Impl> impl;
@@ -335,14 +337,16 @@ class EEngine {
 public:
     // hdr: NGX's IsHDR (linear colour, the exposure textures); lowResMotion: MVLowRes (render-size motion vectors,
     // in render pixels; otherwise output-size motion in output pixels). Render size at most the output size.
+    // autoExposure (HDR): NGX's AutoExposure, the exposure measured from the colour on every second frame instead of
+    // read from images.exposure (needs EModel::hasAutoExposure).
     EEngine(EModel& model, uint32_t renderWidth, uint32_t renderHeight, uint32_t outputWidth, uint32_t outputHeight,
-            bool hdr, bool lowResMotion);
+            bool hdr, bool lowResMotion, bool autoExposure = false);
     ~EEngine();
     EEngine(const EEngine&) = delete;
     EEngine& operator=(const EEngine&) = delete;
     void recordInitialize(VkCommandBuffer command);
     // color (and depth with lowResMotion) at the render size, motion at the render or output size; images.exposure
-    // the game's 1x1 exposure (HDR; 1 when absent). A borrowed RGBA16F finalOutput (GENERAL) is written directly.
+    // the game's 1x1 exposure (HDR without autoExposure; 1 when absent). A borrowed RGBA16F finalOutput (GENERAL) is written directly.
     void setFrame(const FrameImages& images, const EFrameSettings& settings, FrameOutput finalOutput = {});
     // With a timestamp query pool, four stamps are written from query `first`: start, after the input kernel, after
     // the network and after the reconstruction.