Chat sends move 0 value, so the network fee is structurally load-bearing (it's
the only thing that forces a real shielded input; 0-value + 0-fee builds a
degenerate, unrelayable tx). Three gaps addressed:
1. Fee floor — broadcastChatMemos now uses max(getDefaultFee(), kChatMinFeeDrgx),
so a 0 / too-low global default-fee setting can't silently break chat.
2. Real delivery status — the echo was marked Sent on SUBMIT regardless of the
on-chain outcome (the z_sendmany callback was empty), so failures were
invisible and the Retry affordance never fired for async failures. Add a third
ChatDelivery::Sending state (appended so persisted 0=Sent stays valid); record
the echo in-memory as Sending, and resolve it to Sent/Failed from the
z_sendmany completion callback — persisting only the final status (so a restart
never shows a stuck spinner; a stray persisted Sending loads as Sent). A subtle
"sending…" label shows while in flight.
3. Pay-from-funded + pre-check — z_sendmany spends from one z-address, and the
identity reply address may be unfunded while funds sit elsewhere. chatPayFromZaddr
picks a spendable z-address that can cover the fee (preferring the identity
address); the memo still advertises the identity address as reply-to, so paying
from a different note is transport-transparent. If nothing can cover the fee, a
clear "need a small shielded balance" toast replaces the cryptic failure.
Full node only for the callback path; lite resolves optimistically on queue.
8-language strings + CJK subset (+1 glyph 賄).
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>