feat(sprint10): Phase 4+5 — Frontend import wizard + integration testing

Phase 4 — Frontend Import Wizard:
- bank-import.ts service: types (BankImportSession, BankTransaction,
  CsvColumnMapping, ImportSessionStatus, MatchStatus) + 12 React Query hooks
  (sessions, transactions, mappings, upload/confirm/skip/assign/complete)
- /finance/import page: 4-step wizard (Upload -> Map -> Review -> Confirm)
  * Drag-and-drop upload with bank format auto-detect (MT940/CAMT.053/CSV)
  * CSV column mapping editor (saves as reusable mapping)
  * Review table with color-coded MATCHED/SUGGESTED/UNMATCHED/CONFIRMED rows,
    confidence % badges, member-assign Combobox, skip/confirm/bulk-confirm
  * Completion summary + import history table with resume action
- de.json + en.json: full bankImport.* namespace (steps, upload, map, review,
  complete, history, status, sessionStatus, actions, errors)
- Navigation: Finanzen converted to nested submenu (Uebersicht + Import)

Phase 5 — Integration Testing:
- docker compose down -v + up -d --build (clean rebuild)
- Playwright e2e/sprint10-system-test.spec.ts: verifies /finance/import
  unauthenticated -> /login?callbackUrl=%2Ffinance%2Fimport (PASS)
- Backend health + frontend route registration verified

Bugfix bundled (blocked backend startup):
- PaymentRepository: countOverdueByClubId* queries referenced non-existent
  Payment.dueDate column (regression from Sprint 9 Phase 6, commit 57f418f).
  Switched to Payment.periodTo (the implicit due date for billing periods).

cannamanage-frontend/e2e/sprint10-system-test.spec.ts

@@ -0,0 +1,15 @@
+import { test, expect } from "@playwright/test"
+
+test("Sprint 10 — /finance/import redirects unauthenticated user to /login with callbackUrl", async ({
+  page,
+}) => {
+  await page.goto("http://localhost:3000/finance/import", {
+    waitUntil: "domcontentloaded",
+  })
+  await page.waitForURL(/\/login/, { timeout: 15000 })
+  const url = page.url()
+  console.log("Redirected to:", url)
+  expect(url).toContain("/login")
+  expect(url).toContain("callbackUrl")
+  expect(decodeURIComponent(url)).toContain("/finance/import")
+})