Test keywords in place of the CLIP embedding in a file's JSON

clipKeywords takes a file's ML data and whether it is a video, and gives the
titles of the Discover categories of Ente's photos app that its CLIP embedding
falls in, highest score first. The tests cover the rule with made-up vectors
and Ente's real categories with the CLIP embedding of a public-domain photo of
a sunset. The backup and backup-metadata tests now expect keywords in a file's
JSON and no CLIP embedding in its mlData. These tests fail until the
implementation lands.

Model: opus-5-5

test/cli/backup-end-to-end.test.ts

@@ -86,10 +86,17 @@ const DAY = "2024/2024-03/2024-03-01";
 const TOAST = new TextEncoder().encode("a few seconds of the wedding toast");
 
 // Ente's ML data for beach.jpg: a face it found, and the photo's CLIP
-// embedding.
+// embedding, here that of a photo of a sunset (see clip-keywords.test.ts).
 const ML_DATA = {
     face: { faces: [{ faceID: "100_1", score: 0.98 }] },
-    clip: { embedding: [0.5, 0.6, 0.7] },
+    clip: {
+        embedding: JSON.parse(
+            readFileSync(
+                new URL("../clip-keywords-sunset.json", import.meta.url),
+                "utf-8",
+            ),
+        ).embedding,
+    },
 };
 
 // Each file's ID, its owner, its original as uploaded, and the metadata its
@@ -486,7 +493,10 @@ describe("the first backup of the account", () => {
             },
             updationTime: TAKEN,
         });
-        expect(beach.mlData).toEqual(ML_DATA);
+        // The JSON holds the ML data without its CLIP embedding, and the
+        // keywords the embedding gives in its place.
+        expect(beach.mlData).toEqual({ face: ML_DATA.face });
+        expect(beach.keywords).toEqual(["Sunset"]);
         expect(beach.imageMetadata.exif.Make.description).toBe("Canon");
         expect(beach.imageMetadata.exif.Model.description).toBe("EOS R5");
 
@@ -497,6 +507,7 @@ describe("the first backup of the account", () => {
             metadata: { title: "toast.mp4", fileType: "video" },
         });
         expect(toast).not.toHaveProperty("mlData");
+        expect(toast).not.toHaveProperty("keywords");
         expect(toast).not.toHaveProperty("imageMetadata");
         expect(toast).not.toHaveProperty("imageMetadataError");