Fix/dependabot cus feedback (#946)

* feat(bookkeeping): per-account default VAT, oresavrundning momsfri

Add a per-account "Standard moms" setting to the chart of accounts and use
it to auto-fill the moms on a leverantorsfaktura-rad when that konto is
picked. Oresavrundning (3740) ships as "Ingen moms", so a rounding line no
longer inherits the 25 % rad-default and skews the moms.

- chart_of_accounts.default_vat_rate (0/0.06/0.12/0.25, CHECK-constrained)
- BEFORE INSERT trigger ships 3740 momsfri on every insert path; backfills
  existing 3740 rows
- kontoplan editor: dead free-text momskod replaced with a Standard moms select
- supplier-invoice rad auto-fills the rate from the konto default

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

* feat(supplier-invoices): configurable start number for the ankomstnummer series

Add a company_settings.next_arrival_number start floor so a company can continue its leverantorsfaktura numbering from a previous system (e.g. Fortnox) instead of restarting the ankomstnummer at 1. get_next_arrival_number now floors the series via GREATEST(MAX(arrival_number)+1, next_arrival_number), so the floor can never move the series backwards or collide with the (company_id, arrival_number) unique index.

The RPC is hardened while rewritten: SET search_path to empty, schema-qualified refs, and an auth.uid() membership check matching generate_invoice_number.

Includes the settings UI field, sv/en strings, migration, and pg-real coverage. The CompanySettings type and Zod schema field for this feature landed earlier in 1bf3b641 (swept into the per-account VAT commit).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

* fix(dependabot): reduce open pull requests limit and group updates for better management

---------

Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

types/index.ts

@@ -258,6 +258,10 @@ export interface CompanySettings {
   // Invoice settings
   invoice_prefix: string | null
   next_invoice_number: number
+  // Starting ankomstnummer for the supplier-invoice (leverantorsfaktura)
+  // series. Acts as a floor: get_next_arrival_number returns
+  // GREATEST(MAX(arrival_number)+1, next_arrival_number). Defaults to 1.
+  next_arrival_number: number
   next_delivery_note_number: number
   invoice_default_days: number
   invoice_default_notes: string | null
@@ -1394,6 +1398,9 @@ export interface BASAccount {
   is_active: boolean
   is_system_account: boolean
   default_vat_code: string | null
+  // Per-account default VAT rate for booking lines (0/0.06/0.12/0.25).
+  // null = no default (line keeps its own rate). Öresavrundning (3740) = 0.
+  default_vat_rate: number | null
   description: string | null
   sru_code: string | null
   k2_excluded: boolean