As per BOLT recommendation https://github.com/lightning/bolts/pull/1232, this means
we will insist on this being available.
For CLN, we added this in 0.12.0 (2022-08-23), though there were fixes as late as 24.02. Either way that's well outside our support window.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Closes: https://github.com/ElementsProject/lightning/issues/8152
Changelog-Changed: Protocol: We now insist that peers support `option_channel_type` (in CLN since 0.12.0 in late 2022, similar for other implementations).