feat(transactions): show all library templates in picker; fix PSD2 seed-row collision (#596)

* feat(transactions): show all library templates in picker; fix PSD2 seed-row collision

- Booking template picker: surface every active library template, not
  only the convertible 2-account shapes. Multi-leg/complex templates
  route to the manual journal editor pre-filled via applyTemplate
  instead of being hidden. Drop direction filtering for user
  templates (inferred direction is unreliable); the curated static
  catalog still respects it. Add an "Aktivera och bokfor" recovery
  toast for TX_CATEGORIZE_INVALID_ACCOUNT mirroring the existing
  ACCOUNTS_NOT_IN_CHART flow. CreateTemplateForm reflows to one card
  per line so trash buttons stop colliding on narrow screens.

- cash_accounts.upsertFromPsd2: the seed_default_cash_account
  migration plants a manual (bank_connection_id IS NULL) row on the
  same ledger_account, so the first PSD2 sync's upsert on
  (company_id, bank_connection_id, external_uid) cannot match it
  (NULL != NULL) and falls through to INSERT, tripping the
  (company_id, ledger_account) UNIQUE constraint. Look up and
  promote the seed row in place first.

- Tests: pin the TX_CATEGORIZE_INVALID_ACCOUNT error shape the
  recovery toast parses; cover applyTemplate on shapes the
  converter rejects (split-expense and all-'business'-typed).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

* fix(transactions): PR review — currency metadata, MRU ordering, observable promote, BAS validation

- TransactionBookingDialog.buildInitialLinesFromTemplate: attach
  buildCurrencyMetadata to settlement lines for foreign-currency
  transactions so the journal entry retains the original currency,
  amount, and exchange_rate. Without this, non-SEK transactions
  routed through a non-convertible template were recorded in SEK
  only with no foreign-currency annotation. (Greptile #2)

- TemplatePicker.handleSelectLibraryRaw: only bump the MRU after
  confirming the click will actually do something (i.e. converted
  OR a callback is wired). Future consumers that omit
  onPickLibraryTemplate would otherwise corrupt MRU ordering for
  templates the user never successfully applied. (Greptile #1)

- cash_accounts.upsertFromPsd2 promote-seed: add .select('id') so
  a zero-row UPDATE is observable. If the seed row vanishes
  between the SELECT and UPDATE (concurrent ops), fall through to
  the normal upsert instead of silently returning success without
  persisting anything. (Greptile #3, compliance A.8.9)

- transactions/page.tsx TX_CATEGORIZE_INVALID_ACCOUNT toast:
  validate accountNumber against /^\d{4}$/ before embedding in any
  fetch URL/body. Defense-in-depth against a malformed server
  error envelope. (compliance V8.2.1)

- categorize route test: switch the not-in-chart fixture from
  '4535' (Inköp av varor från annat EU-land — reverse-charge) to
  '5420' (Programvaror) so the example doesn't imply a domestic
  override against an EU-reverse-charge account would be valid
  without its paired moms legs. (Swedish compliance review #3)

Other review items deliberately not addressed in this PR:
- Validate-on-save that every VAT-rated template has a 'vat'
  line — overrides existing CreateTemplateForm UX, separate PR.
- vat_rate enum guard in applyTemplate — defensive; the editor
  dropdown only surfaces legal rates and is the only write path
  in production today.
- Imbalance UI warning — already handled: JournalEntryForm
  computes isBalanced and gates submission; DB trigger
  check_journal_entry_balance enforces BFL 5 kap server-side.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

app/api/transactions/[id]/categorize/__tests__/route.test.ts

@@ -714,4 +714,40 @@ describe('POST /api/transactions/[id]/categorize', () => {
     // had to enqueue a response for it. The absence of an enqueue here plus
     // the 400 status is the assertion that the route did not fall through.
   })
+
+  // The transactions page surfaces TX_CATEGORIZE_INVALID_ACCOUNT with an
+  // inline "Aktivera och bokför" toast and reads details.accountNumber to
+  // call POST /accounts/activate. This test pins the error shape that flow
+  // depends on — if the field name changes the recovery UI silently breaks.
+  it('returns 400 TX_CATEGORIZE_INVALID_ACCOUNT with details.accountNumber when account_override is not in the chart', async () => {
+    const tx = makeTransaction({
+      id: 'tx-1',
+      amount: -869.25,
+      merchant_name: 'Paddle',
+      journal_entry_id: null,
+    })
+
+    enqueue({ data: tx, error: null })
+    enqueue({ data: { entity_type: 'enskild_firma', fiscal_year_start_month: 1 }, error: null })
+    // chart_of_accounts lookup for '5420' — not in the company's chart.
+    // Using a plain expense account (Programvaror) avoids the implication
+    // that 4535 (Inköp av varor från annat EU-land, reverse-charge) would
+    // be a valid override on a domestic transaction without its paired
+    // moms legs (2614/2645) — see the Swedish compliance review note.
+    enqueue({ data: null, error: null })
+
+    const request = createMockRequest('/api/transactions/tx-1/categorize', {
+      method: 'POST',
+      body: { is_business: true, category: 'expense_software', account_override: '5420' },
+    })
+    const response = await POST(request, createMockRouteParams({ id: 'tx-1' }))
+    const { status, body } = await parseJsonResponse<{
+      error: { code: string; details: { accountNumber?: string } }
+    }>(response)
+
+    expect(status).toBe(400)
+    expect(body.error.code).toBe('TX_CATEGORIZE_INVALID_ACCOUNT')
+    expect(body.error.details.accountNumber).toBe('5420')
+    expect(mockCreateTransactionJournalEntry).not.toHaveBeenCalled()
+  })
 })