Thumbnail upload PUT sends the signed Content-MD5 (closes #238)

`/files/upload-url` signs the content MD5 into the presigned URL, so
storage refused the PUT that `putFile` sent without it. `putFile` now
takes the MD5 given to `getUploadURL` and sends it. The thumbnail test's
fake storage refuses a PUT without the signed header.

Model: opus-5-5

test/api/client.test.ts

@@ -780,7 +780,7 @@ describe("ApiClient timeouts", () => {
 
         await client.getJSON("/a");
         await client.postJSON("/b", {});
-        await client.putFile("https://s3.example/x", new Uint8Array([1]));
+        await client.putFile("https://s3.example/x", new Uint8Array([1]), "m");
         await client.putJSON("/c", {});
 
         for (const call of calls) {
@@ -825,7 +825,8 @@ describe("ApiClient timeouts", () => {
             [
                 "putFile",
                 () => new Response(null, { status: 200 }),
-                (c) => c.putFile("https://s3.example/x", new Uint8Array([1])),
+                (c) =>
+                    c.putFile("https://s3.example/x", new Uint8Array([1]), "m"),
             ],
             [
                 "getFileStream",
@@ -1049,7 +1050,7 @@ describe("ApiClient error typing", () => {
         const client = new ApiClient({ fetch, retry: noWait });
 
         const err: unknown = await client
-            .putFile("https://s3.example/obj", new Uint8Array([1, 2]))
+            .putFile("https://s3.example/obj", new Uint8Array([1, 2]), "m")
             .catch((e: unknown) => e);
 
         expect(err).toBeInstanceOf(ApiError);
@@ -1067,7 +1068,11 @@ describe("ApiClient error typing", () => {
         );
         const client = new ApiClient({ fetch, retry: noWait });
 
-        await client.putFile("https://s3.example/obj", new Uint8Array([1, 2]));
+        await client.putFile(
+            "https://s3.example/obj",
+            new Uint8Array([1, 2]),
+            "m",
+        );
         expect(calls).toHaveLength(2);
     });
 
@@ -1277,6 +1282,7 @@ describe("ApiClient onRequest", () => {
         await client.putFile(
             "https://s3.example/obj?X-Amz-Signature=abc",
             new Uint8Array([1, 2]),
+            "m",
         );
 
         expect(requests).toEqual([