[Feature Request] give cli startup --configuration-dir

If the qcli can be initialized with different $HOME; i.e. be able to start with `--config-dir` or use env var - then the user can run with different sets of tools/mcps -- and not have to deal with dependency hell among mcp or incompatibility between tools.

Sort of virtual environments for qcli.

I searched the codebase and I think right now the $HOME/.aws/amazonq is fixed

https://github.com/aws/amazon-q-developer-cli/blob/3f26b1f05d1b05106de21474c921ac3b15e62338/crates/chat-cli/src/util/directories.rs#L45

On my laptop, I accomplish sorta the same by using symbolic links; and while it works just fine, I have to switch the symlink to activate different profile

```
rchyla@u0b:~/.aws$ ll
total 188
drwxr-xr-x 6 rchyla domain^users 4096 Aug 22 14:15 ./
drwx------ 96 rchyla domain^users 4096 Aug 22 14:13 ../
lrwxrwxrwx 1 rchyla domain^users 15 Aug 22 14:15 amazonq -> amazonq.default/
drwxr-xr-x 4 rchyla domain^users 4096 Aug 22 14:16 amazonq.default/
drwxr-xr-x 4 rchyla domain^users 4096 Aug 22 14:17 amazonq.mlinfra/
-rw------- 1 rchyla domain^users 15269 Aug 21 13:28 config
-rw------- 1 rchyla domain^users 90608 Aug 21 13:28 credentials
drwxr-xr-x 6 rchyla domain^users 4096 Oct 9 2023 models/
```

I also tried using `.amazonq` and `.aws/amazonq` in the local dir -- but the problem is that qcli will load both the global and the local configuration.

I could try to send a PR, but I'd like to first gauge if such a feature fits into your plans.

Inizia da crates/chat-cli/src/util/directories.rs nel percorso indicato e segui il modo in cui qcli risolve la configurazione globale e locale. Verifica dove viene utilizzata la directory di configurazione e se i test coprono la selezione della directory. Il lavoro è completo quando un’impostazione della riga di comando o dell’ambiente consente di selezionare un insieme di configurazione isolato senza caricare anche la configurazione globale predefinita.

Scritto dal modello di indicizzazione a partire dal testo della issue.