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/theme/page.tsx

@@ -8,6 +8,7 @@ import {
 	saveTheme,
 } from "@/actions/admin-theme";
 import { RenameTheme } from "@/components/admin/theme/rename-theme";
+import { Button } from "@/components/ui/button";
 import { canAccess, getAdminContext, PERMS } from "@/lib/permissions";
 import { siteSettings } from "@/lib/services/site-settings";
 import { listCustomThemes } from "@/lib/theme-custom-store";
@@ -409,9 +410,9 @@ export default async function AdminTheme({
 					{Object.entries(PRESETS).map(([name, palette]) => (
 						<form key={name} action={applyPreset}>
 							<input type="hidden" name="preset" value={name} />
-							<button
+							<Button
 								type="submit"
-								className="btn btn-outline inline-flex items-center gap-2"
+								variant="outline"
 							>
 								<span className="flex items-center gap-1">
 									{[
@@ -435,7 +436,7 @@ export default async function AdminTheme({
 									))}
 								</span>
 								{name}
-							</button>
+							</Button>
 						</form>
 					))}
 				</div>
@@ -458,9 +459,9 @@ export default async function AdminTheme({
 						className="px-3 py-2 rounded-lg border bg-[var(--admin-canvas)] text-[var(--admin-text)] text-sm w-64"
 						style={{ borderColor: "var(--admin-border)" }}
 					/>
-					<button type="submit" className="btn btn-primary">
+					<Button type="submit" variant="default">
 						Save current theme
-					</button>
+					</Button>
 				</form>
 
 				{customThemes.length === 0 ? (
@@ -503,15 +504,15 @@ export default async function AdminTheme({
 								<div className="flex gap-2">
 									<form action={applyCustomTheme}>
 										<input type="hidden" name="id" value={theme.id} />
-										<button type="submit" className="btn btn-sm btn-outline">
+										<Button type="submit" variant="outline" size="sm">
 											Load
-										</button>
+										</Button>
 									</form>
 									<form action={deleteCustomTheme}>
 										<input type="hidden" name="id" value={theme.id} />
-										<button type="submit" className="btn btn-sm btn-danger">
+										<Button type="submit" variant="destructive" size="sm">
 											Delete
-										</button>
+										</Button>
 									</form>
 								</div>
 							</div>
@@ -652,9 +653,9 @@ export default async function AdminTheme({
 						className="w-full font-mono text-sm"
 					/>
 					<div className="mt-4 text-right">
-						<button type="submit" className="btn btn-primary">
+						<Button type="submit" variant="default">
 							{t("saveCss")}
-						</button>
+						</Button>
 					</div>
 				</section>
 			</form>