Manually created transactions can now edit every field (account, date,
amount, description) after creation, not just category/notes/labels.
Imported/bank transactions keep amount, date, account, currency and
description locked to their source data.
- UpdateTransactionRequest validates amount/date/account/currency only
for manually_created transactions, so the fields are dropped for
imported ones.
- On edit, the manual account balance is moved to match a changed
amount/date/account, opt-in via the same update_balance flag as
create/delete; connected accounts are skipped. ManualBalanceAdjuster
gains a shared adjust() primitive and reverseCreatedTransaction().
- The edit dialog unifies create/edit editability behind canEditAllFields
and shows the account/date/amount inputs (and the update-balance
checkbox) when editing a manual transaction.