feat: Get rid of MessageState::{OutPreparing, OutMdnRcvd} in the db

`OutPreparing` is deprecated since 2024-12-07, replace it with `OutDraft` to let the user review
such messages if any. `OutMdnRcvd` is not used in the db for new messages since
a30c6ae1f7, `OutDelivered` is stored instead.

deltachat-ffi/src/lot.rs

@@ -230,7 +230,6 @@ pub enum LotState {
     MsgInFresh = 10,
     MsgInNoticed = 13,
     MsgInSeen = 16,
-    MsgOutPreparing = 18,
     MsgOutDraft = 19,
     MsgOutPending = 20,
     MsgOutFailed = 24,
@@ -246,7 +245,6 @@ impl From<MessageState> for LotState {
             InFresh => LotState::MsgInFresh,
             InNoticed => LotState::MsgInNoticed,
             InSeen => LotState::MsgInSeen,
-            OutPreparing => LotState::MsgOutPreparing,
             OutDraft => LotState::MsgOutDraft,
             OutPending => LotState::MsgOutPending,
             OutFailed => LotState::MsgOutFailed,