refactor(ui): design-system consistency pass over dense pages + i18n de-bloat (#961)

* refactor(ui): normalize dense pages to the locked design system

Sweep of the info-dense surfaces against .claude/rules/design.md; no
behavior changes, classNames and primitive adoption only.

- Replace hand-rolled h1s with PageHeader (import, suppliers, kpi,
  salary/employees, skattekonto, settings layout) and drop the one
  double title (SalarySettingsContent under the settings h1)
- Replace hand-rolled empty states with EmptyState (skattekonto,
  banking/api-keys/oauth/counterparty settings) and hand-rolled
  pulse divs with Skeleton (deadlines, report view loaders)
- Remove semantic colors used as chrome: amber/emerald banners in
  AGIPanel and SkatteverketPanel, success/warning tints in
  kassaflodesanalys, arsredovisning and import become neutral
  surfaces with the tint kept on the icon only
- Full-opacity borders everywhere (border-border/30-60,
  border-destructive/20-40, border-foreground/30, text-destructive/80)
- Snap off-scale spacing (p-5 to p-6, p-2.5 to p-3, gap/mt-x.5 to
  scale values); KPI metric tiles p-6 to p-4 per the tile rule
- Remove the mobile Select that duplicated the invoices status Tabs
  (TabsList already scrolls horizontally); single Tabs now serves
  both breakpoints
- supplier-invoices: shared formatCurrency instead of a local
  formatAmount helper; skattekonto: formatDate/formatDateLong/
  formatDateTime instead of raw dates and toLocaleString
- arsredovisning flerarsoversikt converted to the Table primitive
  with right-aligned tabular-nums cells
- Settings: CardTitle text-base on section cards, one heading idiom
  in AccountSettingsContent, h3 to h2 in CompanyProfileView

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

* refactor(i18n): trim text bloat and fix an untranslated sv string

- Fix invoice_credit.create_failed_fallback: sv catalog carried the
  English "Failed to create credit note"; now "Kunde inte skapa
  kreditfaktura". Translate new_user_checklist.step3_title in en
- Drop descriptions that paraphrase their own title (design.md
  forbidden pattern): invoice_detail.credited_description,
  invoice_credit.original_card_description, invoice_editor
  customer/notes card descriptions (keys deleted from both
  catalogs, zero remaining usages); the transaction booking
  DialogDescription becomes sr-only so screen readers keep it
- Trim redundant sentences from settings_salary.info_payroll_scope,
  settings_backup.intro, ext_cloud_backup_long_description,
  settings.name_description, salary_payments.open_payments_note and
  shorten invoice_credit.reason_card_description; statutory BFL/tax
  prose untouched
- Normalize toast punctuation (dimensions/self_billing
  created_description lose the trailing period like their siblings)
- common.delete "Radera" to "Ta bort" (zero live call sites; Radera
  stays reserved for irreversible account/company deletion)

Catalogs verified key-identical (4795 keys each) and JSON-parseable.

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

---------

Co-authored-by: Claude Fable 5 <noreply@anthropic.com>

DECISIONS.md

@@ -53,3 +53,8 @@ One line per decision: `[YYYY-MM-DD] <decision>: <why>`. Appended by agents and
 [2026-07-09] #917 fix scoped to the current-year suggestion: "Sedan räkenskapsårets början" now resolves from the fiscal_periods row containing today, but the "Föregående räkenskapsårets start" custom option still derives from the recurring fiscal_year_start_month: the issue only covers the current-year date and a first-year company has no previous period row to resolve against.
 [2026-07-09] Issue #919 (duplicate guard should steer to matching): the match action lives INSIDE DuplicateBookingDialog (fetch to /api/reconciliation/bank/link + account resolution via /api/cash-accounts + resolveAccount, exactly the MatchVoucherDialog path) rather than in each call site or a new endpoint: both call sites (transactions page runCategorize + TransactionBookingDialog/JournalEntryForm) share one implementation and pass only the transaction context + an onMatched callback mirroring onLinked. Match is primary ONLY for ledger-only candidates (transaction_id null, the SIE-import case); sibling-transaction candidates keep "Bokför ändå" primary since N:1 matching is the edge case. No lib change: the candidate already carries the transaction_id discriminator, covered by existing tests.
 [2026-07-09] Demo/sandbox users could reach Stripe: an anonymous user on a sandbox company hit POST /api/billing/checkout and created a live Stripe customer (no subscription = no charge; exact tenant/customer IDs kept out of source control, see the incident PR). Root cause: neither billing/checkout nor billing/portal checked is_anonymous or is_sandbox, and withRouteContext lets anonymous users through (they are authenticated, just anonymously). Fix guards BOTH conditions in both routes (is_anonymous is the identity truth; guardSandbox matches the existing lib/sandbox/guard.ts "never charge a token" doctrine), belt-and-suspenders since anon and sandbox happen to co-occur today but are orthogonal. Anon check runs first (in-memory, no DB round trip). Also surfaced isDemo on GET /api/billing/status so the client hides the upgrade CTA instead of showing a button that 403s. Blast radius = exactly one company (no other sandbox/anon tenant had a stripe_customer_id). Left the stray company_subscriptions row + orphan Stripe customer for manual cleanup (prod write / external destructive action, not done unilaterally).
+[2026-07-09] UI consistency pass: skipped the suppliers/page.tsx card-grid to Table conversion (did PageHeader + space-y-8 only): the suppliers.* i18n namespace has no column-header keys (nothing equivalent to customers.col_name/col_type), the pass forbade new i18n keys, and a data table whose primary name column has no header is worse than the existing card grid.
+[2026-07-09] supplier-invoices/[id]: replaced the local formatAmount with shared formatCurrency at all direct render sites, but the two i18n-templated amounts (amount_registered_description embeds "kr", remaining_to_pay embeds "{currency}") now use the shared bare-number formatAmount from lib/utils instead: passing formatCurrency output there would double-print the currency, and message files were off-limits.
+[2026-07-09] common.delete changed "Radera" to "Ta bort": grep proved the key has zero live call sites (every delete dialog uses feature-namespace keys), so this only affects future uses; convention going forward is Ta bort = detach/remove, Radera = irreversible destruction (kept in AccountDangerZone/CompanyDangerZone keys).
+[2026-07-09] InvoiceEditor customer-card description kept only for the self-billing branch (issuer_card_description adds real info: who issues the invoice); the plain-invoice branch dropped its description as a title paraphrase per design.md forbidden patterns.
+[2026-07-09] SalaryCalendar absence-type rainbow palette (red/amber/emerald/blue/indigo pills) left as-is in the UI consistency pass: those colors encode absence categories (data), not status chrome, and swapping them for the 3 semantic tokens would collapse 5 distinguishable categories; needs a proper categorical-palette decision instead of a mechanical fix.