raw: decode the preview already oriented and drop the second turn

Skia's Image.MakeImageFromEncoded applies the embedded JPEG's EXIF
orientation itself. A Panasonic RW2 preview stored 1920x1280 with
orientation 8 therefore decodes as 1280x1920 already — the frame the
camera meant.

previewGrid turned it a second time by its own per-orientation canvas
rotation, so a portrait frame's reference grid met the develop a quarter
turn out, previewMatch rejected the fit as folded and the RW2 opened with
no tone curve at all (~9-13 levels off across the shadows).

Drop the rotation and read the crop rectangle and aspect straight from
bmp.width()/bmp.height(), the display dimensions Skia hands back.

Panasonic RW2 now fits a real curve (dRGB 2.3,-0.0,0.4, was -9.1,-10.3,
-13.2). The five bodies that were already stable — ORF, NEF, DNG, both
RAF — measure exactly as before.

getJpegOrientation had no other caller and goes with it; raw-orf-check
drops its own byte-scanning preview finder, which crashed on DNG and RAF,
and reads the reference through the shipped extractEmbeddedJpeg.

docker/frontend/src/engine/rawDevelop.ts

@@ -212,48 +212,6 @@ async function cameraPreview(raw: LibRaw): Promise<Uint8Array | null> {
   return new Uint8Array(thumb.data);
 }
 
-// Reads EXIF Orientation tag (1-8) from JPEG byte headers.
-export function getJpegOrientation(bytes: Uint8Array): number {
-  if (bytes.length < 12 || bytes[0] !== 0xff || bytes[1] !== 0xd8) return 1;
-  let offset = 2;
-  while (offset < bytes.length - 4) {
-    if (bytes[offset] !== 0xff) { offset++; continue; }
-    const marker = bytes[offset + 1];
-    if (marker === 0xe1) {
-      const length = (bytes[offset + 2] << 8) | bytes[offset + 3];
-      if (offset + 4 + length > bytes.length) break;
-      const exifHeader = String.fromCharCode(...bytes.subarray(offset + 4, offset + 10));
-      if (exifHeader === 'Exif\0\0') {
-        const tiffStart = offset + 10;
-        const littleEndian = bytes[tiffStart] === 0x49 && bytes[tiffStart + 1] === 0x49;
-        const read16 = (o: number) => littleEndian ? (bytes[o] | (bytes[o + 1] << 8)) : ((bytes[o] << 8) | bytes[o + 1]);
-        const read32 = (o: number) => littleEndian ? (bytes[o] | (bytes[o + 1] << 8) | (bytes[o + 2] << 16) | (bytes[o + 3] << 24)) : ((bytes[o] << 24) | (bytes[o + 1] << 16) | (bytes[o + 2] << 8) | bytes[o + 3]);
-        if (read16(tiffStart + 2) !== 0x002a) break;
-        const firstIfdOffset = read32(tiffStart + 4);
-        let dirStart = tiffStart + firstIfdOffset;
-        if (dirStart + 2 > bytes.length) break;
-        const entries = read16(dirStart);
-        dirStart += 2;
-        for (let i = 0; i < entries; i++) {
-          const entryOffset = dirStart + i * 12;
-          if (entryOffset + 12 > bytes.length) break;
-          const tag = read16(entryOffset);
-          if (tag === 0x0112) {
-            const val = read16(entryOffset + 8);
-            return val >= 1 && val <= 8 ? val : 1;
-          }
-        }
-      }
-      break;
-    }
-    if (marker === 0xda || marker === 0xd9) break;
-    const segLen = (bytes[offset + 2] << 8) | bytes[offset + 3];
-    if (segLen < 2) break;
-    offset += 2 + segLen;
-  }
-  return 1;
-}
-
 // Fast pure JS binary scanner to extract embedded JPEG preview from RAW files (ARW, NEF, CR2, CR3, DNG, RAF, RW2, ORF, PEF).
 // Scans for all embedded JPEGs in the RAW file and returns the largest segment (the full-size camera preview).
 export function extractEmbeddedJpeg(buf: Uint8Array): Uint8Array | null {
@@ -437,70 +395,38 @@ function previewGrid(jpeg: Uint8Array, w: number, h: number, n = MATCH_GRID): Ui
   if (!bmp) return null;
   try {
     if (bmp.width() < n || bmp.height() < n) return null;
-    const orient = getJpegOrientation(jpeg);
-    const isSwapped = orient === 5 || orient === 6 || orient === 7 || orient === 8;
-    const orientedW = isSwapped ? bmp.height() : bmp.width();
-    const orientedH = isSwapped ? bmp.width() : bmp.height();
-
+    // The decode above has already turned the preview by its own EXIF
+    // orientation: a 1920x1280 orientation-8 Panasonic preview decodes to
+    // 1280x1920, the frame the camera meant. So these are display dimensions and
+    // the only thing left is to trim them to the develop's aspect. Rotating here
+    // as well — which this did — turned a portrait frame's reference a quarter
+    // turn against the develop it was being fitted to, and the fit was rejected
+    // as folded (see previewMatch), which is why the Panasonic RW2 opened with no
+    // curve at all.
     const targetAspect = w / h;
-    const bmpAspect = orientedW / orientedH;
-    let cropW = orientedW;
-    let cropH = orientedH;
+    const bmpAspect = bmp.width() / bmp.height();
+    let cropW = bmp.width();
+    let cropH = bmp.height();
     if (Math.abs(bmpAspect - targetAspect) > 0.01) {
       if (bmpAspect > targetAspect) {
-        cropW = Math.round(orientedH * targetAspect);
+        cropW = Math.round(bmp.height() * targetAspect);
       } else {
-        cropH = Math.round(orientedW / targetAspect);
+        cropH = Math.round(bmp.width() / targetAspect);
       }
     }
-    const cropX = Math.round((orientedW - cropW) / 2);
-    const cropY = Math.round((orientedH - cropH) / 2);
+    const cropX = Math.round((bmp.width() - cropW) / 2);
+    const cropY = Math.round((bmp.height() - cropH) / 2);
 
     const surface = Skia.Surface.MakeOffscreen(n, n) ?? Skia.Surface.Make(n, n);
     if (!surface) return null;
     const canvas = surface.getCanvas();
-    canvas.save();
-
-    if (orient === 3) {
-      canvas.translate(n, n);
-      canvas.rotate(180, 0, 0);
-      canvas.drawImageRectCubic(
-        bmp,
-        Skia.XYWHRect(bmp.width() - cropX - cropW, bmp.height() - cropY - cropH, cropW, cropH),
-        Skia.XYWHRect(0, 0, n, n),
-        1 / 3,
-        1 / 3
-      );
-    } else if (orient === 6) {
-      canvas.translate(n, 0);
-      canvas.rotate(90, 0, 0);
-      canvas.drawImageRectCubic(
-        bmp,
-        Skia.XYWHRect(cropY, bmp.height() - cropX - cropW, cropH, cropW),
-        Skia.XYWHRect(0, 0, n, n),
-        1 / 3,
-        1 / 3
-      );
-    } else if (orient === 8) {
-      canvas.translate(0, n);
-      canvas.rotate(-90, 0, 0);
-      canvas.drawImageRectCubic(
-        bmp,
-        Skia.XYWHRect(bmp.width() - cropY - cropH, cropX, cropH, cropW),
-        Skia.XYWHRect(0, 0, n, n),
-        1 / 3,
-        1 / 3
-      );
-    } else {
-      canvas.drawImageRectCubic(
-        bmp,
-        Skia.XYWHRect(cropX, cropY, cropW, cropH),
-        Skia.XYWHRect(0, 0, n, n),
-        1 / 3,
-        1 / 3
-      );
-    }
-    canvas.restore();
+    canvas.drawImageRectCubic(
+      bmp,
+      Skia.XYWHRect(cropX, cropY, cropW, cropH),
+      Skia.XYWHRect(0, 0, n, n),
+      1 / 3,
+      1 / 3
+    );
     surface.flush();
     const px = canvas.readPixels(0, 0, {
       width: n,