[BUG] Tab‑completion and inline hints don't work when the default user has a password set via aclfile

Describe the bug

When using an aclfile to set a password for the default user: After connecting with redis‑cli without credentials and performing manual AUTH, tab‑completion and inline syntax hint are no longer available. If redis‑cli is started with credentials at connect‑time (using -a), both tab‑completion and inline hint work as expected. When the aclfile directive is commented out and the default user has no password, tab‑completion and hint also work as expected.

Even though manual COMMAND / COMMAND DOCS return complete valid output, tab‑completion and inline hint stay disabled in the first case.

To reproduce

1. Build Redis 8.10 from source.
2. Create an empty aclfile
3. Enable aclfile in redis.conf and start server
4. Launch redis-cli, add a password for the default user, and run ACL SAVE to save the current user configuration into your aclfile, then exit redis-cli:
5. Launch redis‑cli again(without credentials)
6. Run: AUTH password, type KEYS and test Tab‑completion / inline hint

Workaround test (works): Following the previous steps, launch redis‑cli with credentials, type KEYS to test again, and the Tab‑completion / inline hint works as expected:

Control (works): Comment out aclfile: and restart server (default no password), plain redis‑cli works fine.

Expected behavior

In the case of launching redis‑cli without credentials, after successfully authenticating with AUTH, tab‑completion and inline syntax hint should become usable within the redis‑cli session.

Additional information

• Redis version: Redis 8.10
• OS: WSL2 (Ubuntu 26.04)
• hypothesis：redis‑cli does not reload command metadata after manual AUTH when it's started without credentials, causing missing tab‑completion and inline hint.