fn write_split_tokens(
ns: &str,
tokens: &MuxBusTokens,
) -> Result<Vec<(String, PriorKeychainState)>, StoreError>Expand description
Write all three token fields, each independently chunked
(write_chunked_field). On a later field’s failure, rolls back every
entry every earlier field in this call already wrote — otherwise a
partial failure would leave the three fields holding a mix of old and
new tokens, which is worse than either the old or the new set alone.
On success, returns every entry’s PRE-call state (across all three
fields) so muxbus_save’s SQL-write failure branch can roll all of it
back together too.