quak get and get-thumb on an empty cache stop fetching collections once they find the file (closes #222)

`quak get` and `quak get-thumb` used to wait for a refresh, which on an
empty cache fetched the files of every collection. Now, on an empty
cache, `freshFile` reads the collection list, then one collection's
files at a time, and stops at the first that holds the file. That search
stores nothing. Once the cache holds the account's collections,
`freshFile` refreshes as before and looks the file up in the cache. The
commands fetch the content through the new `Library.originalOf()` and
`Library.thumbnailOf()`, which take the file record itself, since the
store may not hold it.

On an empty cache they no longer print a refresh's progress lines. The
`-q` test that relied on `get` refreshing now runs
`helper fix-missing-thumbnails`.

Model: opus-5-5

test/cli/log.test.ts

@@ -234,13 +234,15 @@ describe("-q", () => {
         });
     });
 
-    // The refresh's progress is left out; the line saying why the command
+    // No album holds file 999, so fixing it fails. The refresh's progress and
+    // the list of failed files are left out. The line saying why the command
     // failed is the fatal one, and it is printed.
     it("prints only the line a failing command exits with", async () => {
-        expect(await quak("-q", "get", "999")).toEqual({
+        const fix = ["helper", "fix-missing-thumbnails", "--file", "999"];
+        expect(await quak("-q", ...fix)).toEqual({
             code: 1,
             stdout: "",
-            stderr: "File 999 not found\n",
+            stderr: `quak: 1 file(s) failed; see the "Failed files:" list, or the JSON with --json\n`,
         });
     });