fix(periodisering): stop overselling automatic periodization to enskild firma (#1730)

* fix(bokslut): honest periodisering for enskild firma (K1)

Stop mis-selling automatic periodisering to sole traders and give the
auto-detect a materiality floor:

- Remove the inert PeriodiseringAutoDetectToggle (write-only localStorage,
  no reader anywhere); the settings row is now a plain link to the
  periodisering wizard, with new i18n keys in sv+en.
- Auto-detect tags suggestions under 5 000 kr as low confidence with the
  reason 'Under 5 000 kr: behöver normalt inte periodiseras', citing K1
  (BFNAR 2006:1) for enskild firma and K2 for aktiebolag; the wizard only
  pre-ticks high-confidence rows, so under-floor posts land unticked.
  Personnel-cost lines (7xxx) are exempt: they must always be accrued.
- The accruals GET route resolves companies.entity_type and threads it to
  the detector.
- Per-line accrual hint in the invoice editors is entity-aware: new
  accruals.k1_hint (K1, förenklat årsbokslut) for EF, k2_hint stays for AB.
- Periodisering wizard and year-end AccrualsStep relabel Revisionsarvode
  to Bokslutsarvode for EF, default the liability account to 2991 instead
  of 2992, and show a muted K1-floor intro line.

All copy stays advisory (behöver normalt inte, never får inte):
entity_type is a proxy since no förenklat-vs-full-årsbokslut flag exists.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

* fix(bokslut): SEK-correct materiality floor, entity-type via settings, narrower personnel exemption

Review fixes on the K1 periodisering branch:

- The 5 000 kr floor now compares a SEK amount: queries select currency
  and subtotal_sek, the floor uses the periodisation share of
  subtotal_sek for foreign-currency invoices, and is skipped entirely
  when no SEK amount is resolvable (accrual-k2-hint precedent,
  DECISIONS.md 2026-07-26).
- The accruals route resolves entity type via getCompanyEntityType
  (company_settings-primary, companies fallback) instead of reading
  companies.entity_type directly.
- The personnel-cost exemption from the floor is narrowed from
  startsWith('7') to /^7[0-6]/: 78xx/79xx are not personnel costs.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

---------

Co-authored-by: Jakob Wennberg <311770904+jakobwennberg-oss@users.noreply.github.com>
Co-authored-by: Claude Fable 5 <noreply@anthropic.com>

components/bookkeeping/__tests__/accrual-k2-hint.test.ts

@@ -1,6 +1,7 @@
 import { describe, it, expect } from 'vitest'
 import {
   K2_ACCRUAL_THRESHOLD_SEK,
+  accrualHintKey,
   resolveAccrualAmountSek,
   shouldShowK2AccrualHint,
 } from '@/components/bookkeeping/accrual-k2-hint'
@@ -103,3 +104,18 @@ describe('shouldShowK2AccrualHint', () => {
     ).toBe(false)
   })
 })
+
+describe('accrualHintKey', () => {
+  it('cites K1 (BFNAR 2006:1) for enskild firma', () => {
+    expect(accrualHintKey('enskild_firma')).toBe('k1_hint')
+  })
+
+  it('cites K2 for aktiebolag', () => {
+    expect(accrualHintKey('aktiebolag')).toBe('k2_hint')
+  })
+
+  it('keeps the K2 default when the entity type is unknown', () => {
+    expect(accrualHintKey(null)).toBe('k2_hint')
+    expect(accrualHintKey(undefined)).toBe('k2_hint')
+  })
+})