CLI: add PartialAccount support

After implementing PartialAccounts into DataStore in https://github.com/0xMiden/miden-client/pull/1438, there are some Web Client functionalities that were left with their PartialAccount functionality left as pending.

It would also be a good idea to bundle this changes with renaming of some functions, such as `Client::get_account` to `Client::get_account_record`.

[Original discussion](https://github.com/0xMiden/miden-client/pull/1438#discussion_r2586166854)

Closes 0xMiden/web-sdk#95

Look at the linked PR #1438 in the miden-client repo to understand the PartialAccount implementation in DataStore. In the web-sdk, find the Client class and identify functions like get_account that need renaming to get_account_record and need PartialAccount support. Check existing tests for account handling to see what changes are required. Verify changes by running the CLI tests.

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