Dynamically derive the network for connecting the wallet

The wallet adapter only supports `WalletAdapterNetwork::Testnet` variants.
This means that connecting the wallet on devnet / localhost will result in an incorrect (`mtst`-prefixed) bech32 encoding of the `Address`.

Needs https://github.com/demox-labs/miden-wallet-adapter/issues/38

_Originally posted by @mmagician in https://github.com/0xMiden/miden-faucet/pull/100#discussion_r2388442303_

The issue references a dependency on an external wallet adapter issue (#38 in demox-labs/miden-wallet-adapter). First, examine the current wallet adapter usage in the codebase to understand how WalletAdapterNetwork::Testnet is hardcoded. Then, check the linked upstream issue to see if the necessary changes are available. The goal is to dynamically detect the network (devnet/localhost) and adjust the bech32 address encoding accordingly, likely in the wallet connection logic.

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