mppx@0.4.12

Patch Changes

• 5684b94: Fixed settleOnChain and closeOnChain to use the payee account as
  msg.sender instead of the fee payer when submitting fee-sponsored
  transactions. Previously, sendFeePayerTx used the fee payer as both
  sender and gas sponsor, causing the escrow contract to revert with
  NotPayee(). Added account option to tempo.settle() so callers can
  specify the signing account separately from the fee payer.
• 3bc8657: Added compile-time guard to tempo.session() and tempo.charge(). Unknown properties (e.g. stream instead of sse) now cause a type error instead of being silently accepted.
• 0531edd: Added split-payment support to Tempo charge requests, including client transaction construction and stricter server verification for split transfers.
• 6188184: Added realm auto-detection from the request Host header when not explicitly configured. Resolution order: explicit value → env vars (MPP_REALM, FLY_APP_NAME, VERCEL_URL, etc.) → request URL hostname → "MPP Payment" fallback with a one-time warning. Removed the hard-coded "MPP Payment" default and deprioritized HOST/HOSTNAME env vars in favor of platform-specific alternatives.
• ba79504: Return 410 ChannelClosedError instead of 402 AmountExceedsDepositError when a channel's on-chain deposit is zero but the channel still exists (payer is non-zero). This handles a race window during settlement where the escrow contract zeros the deposit before setting the finalized flag.