quak login --server: log in to a self-hosted Ente server (closes #243)

`quak login` takes the server's API address from `--server` or
`QUAK_SERVER`. `isServerAddress` refuses anything but an http or https
URL with no query or fragment, there and in `Client.fromJSON`. The
client's snapshot keeps a non-default `apiOrigin`, so the session file
names the server and every later command uses it.

Two servers can give two accounts, and two files, the same ID. A
self-hosted account's default cache directory therefore names the
server, and `metadata.json` records it: `Library.open` deletes a cache
from another server whole. `originalOf` and `thumbnailOf` record the
account in a cache that names none before storing a file, and `open`
treats a cache with no collection as empty. This fixes
#254 (closes #254).

Model: opus-5-5

bin/quak.ts

@@ -74,7 +74,11 @@ const context = (): CliContext => ({
     sessionDir: paths.data,
     cacheDir: program.opts<ProgramOptions>().cacheDir,
     loadSession: (path) => loadSession(path, logRequests(log())),
-    login: (opts) => Client.login({ ...opts, apiOptions: logRequests(log()) }),
+    login: (opts) =>
+        Client.login({
+            ...opts,
+            apiOptions: { ...opts.apiOptions, ...logRequests(log()) },
+        }),
     prompt: (message) => input({ message }),
     promptSecret: (message) => password({ message, mask: true }),
 });
@@ -85,7 +89,12 @@ const run = (command: Promise<number>): Promise<void> =>
 program
     .command("login")
     .description("Log in to an Ente account and save the session")
-    .action(() => run(loginCommand(context())));
+    .option(
+        "--server <url>",
+        "Address of a self-hosted Ente server's API, saved with the session " +
+            "(default: QUAK_SERVER, then Ente's hosted service)",
+    )
+    .action((opts: { server?: string }) => run(loginCommand(context(), opts)));
 
 program
     .command("whoami")