Feature request: Add maximum fee sat/vbyte option for Lightning to On-Chain balance conversion

[jurjendevries]

Currently, coinos allows users to automatically convert their Lightning balance to on-chain when a certain threshold is reached. However, there is no option to set a maximum fee in sat/vbyte for this conversion. This can lead to unexpectedly high fees during times of network congestion, which is not ideal for users who want to control their costs.

Proposed Solution
Add an optional maximum fee field (in sat/vbyte) to the Autowithdrawal settings. This way, users can specify the highest fee they are willing to pay for the conversion. If the current network fees exceed this maximum, the conversion can be delayed until fees are within the user's specified limit. Optionally the user can receive a notification.

Example Use Case
A user sets a threshold of 1000000 sats for Autowithdrawal threshold and a maximum fee of 10 sat/vbyte. If the network fees exceed 10 sat/vbyte when the threshold is reached, the conversion will not proceed until fees are below this limit.
When the notification for this is on, the user will receive a notification.

[igorbastosib]

I think it is an old request that brought lots of discussion, it was even implemented once, but caused lots of confusion and it was removed.

I agree that it is a nice feature and should be re-implemented.

If it helps:
Fix the default fee as the medium, so if the user doesn't configure it and the threshold is reached, it auto-withdraw doesn't matter the medium network fee;
An "Advanced" button is added bellow the current configuration allowing user to specify a custom s/vB, so in case user changed this value, instead auto-withdraw only by threshold, it would also check the custom s/vB fee user filled in.

[RafaelEstevamReis]

The biggest problem with custom is that even though the user has the option to wait, coinos gets stuck with UXTO waiting