library: stand a frame up in the catalogue, wall, strip and studio

The library stage carried no way to correct a frame shot on its side, and
nothing kept the correction. A quarter turn now rides on the catalogue row
(`rot`, beside `star`, carried over by a rescan), the two chips under the
preview step it, and the tile, the strip thumbnail and the stage all read it
through one bake so a frame is never stood on its side in one place and
upright in another. The studio opens a frame at that angle and a turn made
there is filed straight back onto the row, so either end of the turn is
what the frame comes up at next time.

docker/frontend/src/engine/library.ts

@@ -102,6 +102,11 @@ export interface LibraryPhoto {
   // it one. It belongs to the catalogue and not to the disk — nothing about the
   // file changes — so a rescan carries it over, the way it carries `addedAt`.
   star?: number;
+  // The quarter turn the reader gave the frame so it stands the way they saw
+  // it, 0 or absent for a frame they have not turned. Like the score it belongs
+  // to the catalogue rather than to the disk — nothing about the file changes —
+  // and a rescan carries it over; the studio opens a frame at this angle.
+  rot?: 0 | 90 | 180 | 270;
   addedAt: number;
 }
 
@@ -913,6 +918,7 @@ export async function scanFolder(
       size: file.size,
       mtime: file.lastModified,
       star: seen?.star,
+      rot: seen?.rot,
       addedAt: seen?.addedAt ?? Date.now(),
     };
     batch.push(row);
@@ -1560,6 +1566,19 @@ export async function setStar(id: string, star: number): Promise<void> {
   }
 }
 
+// The quarter turn a frame stands at, in the same read-and-put the score uses:
+// the catalogue's own, carried over by a rescan, and what the studio opens the
+// frame at.
+export async function setRotation(id: string, rot: 0 | 90 | 180 | 270): Promise<void> {
+  const photo = await getPhoto(id);
+  if (!photo) return;
+  try {
+    await ask(PHOTOS, 'readwrite', (s) => s.put({ ...photo, rot }));
+  } catch {
+    // Private mode: the turn lives no longer than the visit.
+  }
+}
+
 // The frame itself, at last: nothing is read from the disk until this runs, so
 // the catalogue costs thumbnails and no more.
 export async function readPhotoFile(photo: LibraryPhoto): Promise<File> {