feat(rpc): expose the ride-cancel auto-release window in get_chain_info

[MehranMazhar]

ride_auto_release_secs is a genesis-committed consensus parameter that decides who receives money — past the window a RideCancel pays the driver rather than refunding the passenger — and it was not observable from outside the node.

Two consequences, both real:

• An operator could not confirm which value a chain actually runs. Enabling it on stage today, the only way to check was reading the node's own config file on the host, which is the config rather than the committed state. The one external signal was that all three nodes still peered, and that proves they agree — not what they agree on.
• A client could not tell a rider how long a cancel still refunds them. That is a number a passenger-facing app should arguably show, and it had no way to obtain it.

get_chain_info already carries chain_id, tx_fee, both referrer rates and mint_authority; this belongs with them. 0 means the chain does not auto-release at all, which is the default and is what every chain before today ran.

Deliberately not adding mint_cosigners or mint_threshold in the same change — those are security-relevant and worth deciding on their own merits rather than being carried along.

🤖 Generated with Claude Code