fix(pd): look up listenaddr from tm rpc

[conorsch]

When joining a testnet, pd will inspect the RPC endpoint for the bootstrap node and copy its known peers into the generated Tendermint config. To date, since #1847, that logic has also interpolated an incorrect address for the bootstrap node (by default currently testnet.penumbra.zone:26657): the RPC address shouldn't be used, the P2P address should be. This is particularly important when as we move toward updating our configs to default to HTTPS: we can no longer assume that the host portion of a service URL will be the same between the RPC and P2P endpoints. Instead, let's use the RPC to inspect what the correct ListenAddress is.

Testing and review

First, verify the misbehavior on main branch:

git checkout main
cargo run --release --bin pd -- testnet unsafe-reset-all
cargo run --release --bin pd -- testnet join https://rpc.testnet.penumbra.zone
grep ^seed ~/.penumbra/testnet_data/node0/tendermint/config/config.toml

Observe that the first host in there is rpc.testnet.penumbra.zone:26656, which won't work: 26656 isn't even open on that IP. Next, try it on this feature branch:

git checkout smarter-seed-addr-lookup
cargo run --release --bin pd -- testnet unsafe-reset-all
cargo run --release --bin pd -- testnet join https://rpc.testnet.penumbra.zone
grep ^seed ~/.penumbra/testnet_data/node0/tendermint/config/config.toml

Observe that the first host in there is no longer a DNS name, but an IP address. Critically, the IP address is not the same as that for the RPC service:

❯ host rpc.testnet.penumbra.zone
rpc.testnet.penumbra.zone has address 34.111.241.130

Instead, the first node in the TM config should be 35.226.255.25:26656, which maps to the exposed p2p port for the tendermint service on fn-0 in the testnet deployment.

[zbuc]

LGTM!