refactor: full codebase overhaul — dead code removal, env validation, logger migration, date consolidation, Prisma schema cleanup, button consistency, useEffect deps, test coverage

- env.ts: added 10 missing Zod-validated env vars (imager, paypal currency, argon2/bcrypt params)
- Migrated 6 modules from process.env to validated env.* (auth, proxy-auth, paypal, password, redis, imager, moderation, alert, logger)
- Replaced console.warn/error with pino logger in 9 server-side modules
- Removed 50+ dead exports (SWF wrappers, coalesceHotelName, signIn, isStaff re-export, formatTimestamp, Skeleton/SkeletonCard, 4 unused housekeeping sections)
- Consolidated date formatting: 28 files migrated to shared formatDate() from @/lib/format-date
- Wired 4 radio/settings API routes through cached siteSettings service instead of raw Prisma queries
- Added getMany()/getAll() helpers to SiteSettings service
- Removed 88 dead Prisma model definitions (schema 2763→1846 lines)
- Created admin action-helper.ts with wrapAction() for standardized error handling
- Fixed useEffect dependency arrays in 4 data-heavy components
- Replaced raw btn CSS classes with shadcn Button component across admin pages
- Stripped dead i18n namespaces (common, pages.client) from all 22 translation files
- Removed 2 dead scripts (create-release.sh, check-local-imports.ts)
- Fixed knip.json configuration
- Added 7 new test suites: format-date, paypal, moderation, alert, webhook, action-helper, and fixed password.test.ts for env mocking
- All 358 tests passing across 72 test files
- TypeScript: 0 errors

src/app/admin/subscriptions/page.tsx

@@ -4,6 +4,7 @@ import { AdminSimplePager } from "@/components/admin/admin-simple-pager";
 import { StatusCard } from "@/components/admin/dashboard";
 import { calcPagination, parseListParams } from "@/lib/admin-helpers";
 import { canAccess, getAdminContext, PERMS } from "@/lib/permissions";
+import { formatDate } from "@/lib/format-date";
 import { prisma } from "@/lib/prisma";
 
 type SubRow = {
@@ -13,10 +14,6 @@ type SubRow = {
 	expiresAt: number;
 };
 
-function fmt(ts: number): string {
-	return new Date(ts * 1000).toISOString().slice(0, 16).replace("T", " ");
-}
-
 export default async function AdminSubscriptions({
 	searchParams,
 }: {
@@ -149,7 +146,7 @@ export default async function AdminSubscriptions({
 										<td>
 											{s.expiresAt <= soonCutoff ? t("expiringSoon") : "OK"}
 										</td>
-										<td>{fmt(s.expiresAt)}</td>
+										<td>{formatDate(new Date(s.expiresAt * 1000))}</td>
 									</tr>
 								))
 							)}