Fix all TypeScript errors: restore proper types and typed route casts

- Restore `as any` casts for Next.js typedRoutes on dynamic routes
- Use proper types for PDF templates, invoice/expense data, DB schema
- Fix PgColumn casts in sort helpers for expenses/invoices
- Add null guards for optional port/client in record-export
- Fix vitest config (remove invalid poolOptions)
- Lint: 0 errors, TypeScript: 0 errors

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

vitest.config.ts

@@ -8,9 +8,6 @@ export default defineConfig({
     include: ['tests/unit/**/*.test.ts', 'tests/integration/**/*.test.ts'],
     exclude: ['tests/e2e/**', 'node_modules/**'],
     pool: 'forks',
-    poolOptions: {
-      forks: { maxForks: 4 },
-    },
     coverage: {
       provider: 'v8',
       reporter: ['text', 'lcov', 'json-summary'],