fix(transactions): resolve bank account from cash_account_id in booking dialog (#769)

* feat(transactions): expose cash_account_id in list API response

Add cash_account_id to the transactions list API select so that components
can resolve the bank account from the transaction instead of hardcoding.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Signed-off-by: Jonas Flodén <jonas@floden.nu>

* feat(cash-accounts): extract resolveAccount to shared utility

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Signed-off-by: Jonas Flodén <jonas@floden.nu>

* refactor(transactions): use shared resolveAccount in MatchVoucherDialog

Replace the local resolveAccount function with the shared utility from
lib/cash-accounts/resolve-account, reducing code duplication and improving
maintainability.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Signed-off-by: Jonas Flodén <jonas@floden.nu>

* fix(transactions): resolve bank account from cash_account_id in booking dialog

Replaces the hardcoded '1930' bank leg in TransactionBookingDialog with
the actual ledger_account of the transaction's cash account. Companies
with multiple bank accounts (e.g. 1930 + 1940) now get the correct
account pre-filled in both the blank and template-based booking flows.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Signed-off-by: Jonas Flodén <jonas@floden.nu>

* fix(transactions): cancel stale cash-account fetch on dialog re-open

Signed-off-by: Jonas Flodén <jonas@floden.nu>

* fix(transactions): prevent form remount discarding edits during bank account fetch

Hold JournalEntryForm render until the /api/cash-accounts fetch resolves by
changing bankAccount state to string | null (null = pending). This prevents the
form from mounting with key '…-1930', then immediately remounting with the
correct account key and losing any user edits made in the sub-100ms window.
Also adds r.ok guard before parsing and sets '1930' as explicit catch fallback.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Signed-off-by: Jonas Flodén <jonas@floden.nu>

* fix(transactions): cancel stale cash-account fetch in MatchVoucherDialog

Pass a signal object into loadCandidates and return a cleanup from the useEffect
so a stale in-flight fetch (from a previous transaction) cannot call
setAccountNumber/setAccountFallback/setGlLines/setSelected after the dialog
re-opens for a different transaction. Also adds r.ok check before parsing
/api/cash-accounts response.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Signed-off-by: Jonas Flodén <jonas@floden.nu>

---------

Signed-off-by: Jonas Flodén <jonas@floden.nu>

app/api/transactions/route.ts

@@ -64,7 +64,7 @@ export async function GET(request: Request) {
 
   let query = supabase
     .from('transactions')
-    .select('id, date, description, amount, currency, amount_sek, exchange_rate, reference, journal_entry_id, reconciliation_method, is_ignored')
+    .select('id, date, description, amount, currency, amount_sek, exchange_rate, reference, journal_entry_id, reconciliation_method, is_ignored, cash_account_id')
     .eq('company_id', companyId)
 
   // unmatched and reconciled are mutually exclusive — unmatched wins if both set