[Bounty] Add an SDK Example for multisig address

[Thoralf-M]

Please read the README first.

Summary

Add an example that create a multisig address with multiple keys, then gets funds to it and signs a transaction using multiple keys from this address. Similar to https://github.com/Thoralf-M/iota-examples/blob/main/wallet/transactions/multisig.ts

Estimated complexity

Easy

Estimated duration

1 hour

Details & acceptance criteria

• Add example to rust
• Add example to all bindings

Pull request required?

Yes

[David-code-tang]

Claiming this bounty. I will add a multisig address example in Rust and matching examples for all bindings (Python/Go/Kotlin), including funding and multi-key signing flow.

[David-code-tang]

Done: opened implementation PR for this bounty.\n\n- PR: https://github.com/iotaledger/iota-rust-sdk/pull/571\n\nIt adds a multisig address example in Rust and all bindings (Python/Go/Kotlin), including committee creation, multisig address derivation, faucet funding, multi-signature aggregation, and transaction execution.