fix: implicit bitcoin and dogecoin setup when passing node addresses

[marc0olo]

Summary

Passing --bitcoind-addr or --dogecoind-addr did not fully set up the required environment. The bitcoin/dogecoin features were not enabled, so the bitcoin and dogecoin canisters were never deployed despite connecting to the nodes. Users had no way to enable these features through the CLI, making the flags effectively broken.

Additionally, --bitcoind-addr and --dogecoind-addr only accepted raw IP addresses (SocketAddr), which prevented using hostnames like bitcoind:18444 in Docker Compose setups.

Changes

• Automatically enable bitcoin / dogecoin features in the ICP configuration when the respective node addresses are provided, so the canisters actually get deployed
• Automatically enable the II subnet when bitcoin or dogecoin node addresses are provided, as it provides tECDSA signing keys commonly needed for Bitcoin/Dogecoin transactions
• Explicitly create the bitcoin subnet when node addresses are provided for clarity
• Change --bitcoind-addr and --dogecoind-addr from SocketAddr to String and resolve via DNS lookup at startup, enabling hostname support (e.g. Docker service names)