feat(bookkeeping): verifikationsserie per bankkonto for bank-transaction bookings (#2160)

* feat(bookkeeping): verifikationsserie per bankkonto for bank-transaction bookings

A company running several bank accounts (main bank on A, company card on M,
both imported via CSV) could not route each account's bookings into its own
series: every bank_transaction booking took the single company-wide default
from default_voucher_series_per_source_type.

- cash_accounts.voucher_series (nullable, single letter): per-account override,
  editable under Inställningar → Bokföring → Verifikationsserier per bankkonto
  (new PATCH /api/cash-accounts/[id]).
- resolveCashAccountVoucherSeries(): step 2 of the resolution order
  (explicit pick → account override → per-type map → A). Wired into the book
  route and createTransactionJournalEntry, which covers categorize, the agent,
  pending operations and the v1 API.
- Booking dialog gets the series picker, seeded from the server via
  /voucher-sequences/next?source_type&cash_account_id so dialog and route can
  never disagree. An unresolved embedded picker omits voucher_series so a
  stray 'A' never overrides the account's series.

Scope: bank_transaction bookings only. Invoice settlements matched from the
bank keep their payment series; bulk-book resolves inside its RPC (see
DECISIONS.md).

Migration applied to staging as 20260902121420.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01JWSLbQc3jgpfqnxWe6nteh

* fix(bookkeeping): audit and document the per-bankkonto series, tighten preview and PATCH

Consolidated pass over the PR #2160 findings (skeptics, CodeRabbit, Swedish
compliance review):

- Behandlingshistorik (BFNAR 2013:2 p. 9.16): changing cash_accounts.voucher_series
  is a behandlingsregel that outranks the audited per-type map. New trigger
  audit_cash_accounts_voucher_series (UPDATE only, WHEN the series changes, so
  bank-sync churn never logs), cash_accounts added to AUDITED_TABLES and the
  audit_log filter, "Bankkonto ... Verifikationsserie: (tomt) -> M" events in
  the report, pg-real test. Applied to staging as 20260902124513.
- Systemdokumentation (p. 9.2-9.15): revision/systemdokumentation.json gains a
  verifikationsserier_regler block with the resolution order and the two
  exceptions (invoice settlements, samlingsverifikat); the per-account mapping
  itself is in data/cash_accounts.json.
- Settings picker uses the same closed list as the manual verifikat form
  (presets plus letters already in use) instead of all 26 letters; strings
  moved to messages/sv.json and messages/en.json.
- /voucher-sequences/next applies the account override only for
  source_type=bank_transaction (CodeRabbit), so a manual-entry preview cannot
  show a series the entry will not get.
- Book route resolves the series from the account the row ends up on after a
  stranded-row repoint, not the stale one.
- PATCH /api/cash-accounts/[id] answers 404 for a non-UUID id instead of a
  Postgres cast 500; the series lookup logs a warning when it fails open.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01JWSLbQc3jgpfqnxWe6nteh

---------

Co-authored-by: Claude Fable 5.1 <noreply@anthropic.com>

DECISIONS.md

@@ -1483,6 +1483,7 @@ One line per decision: `[YYYY-MM-DD] <decision>: <why>`. Appended by agents and
 [2026-09-01] ENABLE_BANKING_SANDBOX removed from the enable-banking manifest and the index.ts header (#2131): the variable was declared as optional but never read anywhere; sandbox vs production is decided by ENABLE_BANKING_API_URL (api.tilisy.com vs api.enablebanking.com, api-client.ts derives isSandbox from the host). A dead variable declared in the manifest is what the self-hosting docs would otherwise have copied. The manifest now lists the two optional variables the code actually reads (API_URL, PSU_TYPE); the _PRODUCTION aliases stay undeclared on purpose, they are a hosted Vercel convention, not an operator contract.
 [2026-09-02] Repo-wide bloat sweep (chore/bloat-sweep-2026-09): removed dead files/exports/types/i18n namespaces and deduplicated byte-identical helpers into canonical homes (lib/utils chunk/sleep/utcDateStamp, lib/dates/iso, lib/invariants/uuid, lib/xml/escape, lib/reports/sru/format, lib/pdf/number-text pdfAmount/formatDateSv, lib/browser/panel-request, lib/api/v1/body + v1ValidationError, lib/bookkeeping/booking-template-schemas). Deliberately NOT done: naive Math.round(x*100)/100 helpers were not swapped for roundOre (behaviour change at half-ore values, ratchet campaign owns it); lib/bokslut/rounding.ts shim kept because money.test.ts asserts the back-compat re-export; text-based v1 body parsers (empty body allowed) kept inline because readV1JsonBody has different empty-body semantics; the four HTTP endpoints with no first-party caller (skatteverket agi/underlag + agi/sparad DELETE, invoice-inbox items/:id/history, mail connections/backfill) stay because removing a reachable endpoint is a surface change; VacationBalanceCard deleted as unreachable since #1130, the v1/MCP vacation-year-close routes stay.
 [2026-09-01] PR #2130 security-scan round: the register's djuplank is validated (https + skatteverket.se host) before it is returned or navigated to, since the settings page follows it; a contested org number now WITHDRAWS an already-recorded grant nightly (not only blocks new ones), outside the downgrade guards on purpose. NOT done: proof of org-number ownership (Bolagsverket firmatecknare / BankID) before any ombud grant; the org number is tenant-editable across the product (AGI, invoices, årsredovisning) and binding it to a verified identity is a product decision for Emil, tracked as a follow-up rather than declined.
+[2026-09-02] Verifikationsserie per bankkonto applies to bank_transaction bookings only (book route, categorize, agent, pending operations), not to invoice settlements matched from the bank or to bulk-book samlingsverifikat: invoice_paid/supplier_invoice_paid series describe the payment kind and match-* routes have eight builder branches that do not take a series; bulk-book resolves its series inside the bulk_book_transactions RPC. One predictable rule beats partial coverage; extend later if a user asks.
 [2026-09-02] Grok custom connectors are allowlisted by the exact callback https://grok.com/connectors-oauth-exchange-code/ (trailing slash optional), not a grok.com prefix: the value is published by X Corp at docs.x.com/x-ads-api/mcp ("Grok (web)" redirect URL) and grok.com serves the path itself (slash form 308s to no-slash on the same origin), and a prefix would let any future grok.com path receive authorization codes. Grok gets side doors next to ChatGPT (onboarding) and a row under "Other clients" (settings); Claude stays the visual primary per the 2026-08-27 founder call. No new client marker plumbing: the settings URL uses the existing ?client= param with value grok.
 [2026-09-02] Viewer write gate as ONE table-level trigger (enforce_company_writer_role) instead of re-emitting 15 SECURITY DEFINER bodies and ~130 policies: keyed on the JWT role claim so it fires inside definer functions too; no-op for service_role and trigger cascades. agent_conversations/agent_messages and telemetry tables deliberately excluded.
 [2026-09-02] Posting-integrity guards key on current_user IN ('anon','authenticated'), not the JWT claim: inside SECURITY DEFINER RPCs current_user is the definer, so commit_journal_entry, SIE import, storno and rättelse keep working while direct PostgREST manipulation of posted vouchers is blocked. Residual: a direct draft->posted flip may still reuse an unused number below the sequence high-water mark.