1) Yes
2) Currently, after the Keychat wallet receives a Lightning payment, it is stored as Cashu ecash sats. Users can choose which ecash mint to use.
3) Except for the Keychat relay, which is run by us, Keychat is a local app. We also don’t operate any Cashu mint. And no matter which Cashu mint you use, the operator cannot see your cash flow — that’s precisely the point of ecash.