Expose zero-fee-commitment (0FC) channels once ldk-node ships #660 #96

We integrate orange-sdk in a sweep-everything mobile wallet and have been building the unilateral-exit / recovery path for when the LSP is permanently offline. We validated on Mutinynet (details: lightningdevkit/ldk-node#987) that zero-fee-commitment (0FC) channels resolve this cleanly: the keyless P2A anchor lets a user restore their channel backup and CPFP the force-close with any fee UTXO — no per-channel reserve on the phone, no keyed-anchor tooling. On legacy anchors the same exit needs seed-derived keyed-anchor CPFP, which is materially harder.

0FC support landed in ldk-node main (lightningdevkit/ldk-node#660, merged) as AnchorChannelsConfig::enable_zero_fee_commitments. It is currently main-only / unreleased.

Ask (no urgency — tracking)

Once ldk-node cuts a release including #660, please:

1. bump orange-sdk's ldk-node pin to it, and
2. surface enable_zero_fee_commitments through the wallet-creation config so integrators can opt channels into 0FC.

We're happy to open the PR for both when the release is available — filing now so it's on the roadmap. We are not asking you to pin an unreleased ldk-node.

Why it matters to us

The keyless P2A anchor is the difference between a recovery tool that works from a backup + any user UTXO, versus one that must derive keyed-anchor signatures per channel. It directly unblocks a self-custody emergency-exit feature for our wallet class.

Related: lightningdevkit/ldk-node#987 (our 0FC validation), lightningdevkit/ldk-node#660 (the feature), #95 (the failure class this closes for us).