Fix build: resolve Turbopack client bundle and font issues

- Move EXPENSE_CATEGORIES to ~/lib/expense-categories.ts to break
  server router import chain from client component
- Use inline import() types in trpc/react.tsx to prevent Turbopack
  from including server modules (pg, db) in the client bundle
- Replace next/font/google with system font stacks to fix build
  failures in environments without Google Fonts access

https://claude.ai/code/session_012sqEgNQpx676isepeoX4Mi

src/lib/expense-categories.ts

@@ -0,0 +1,11 @@
+export const EXPENSE_CATEGORIES = [
+  "Travel",
+  "Meals & Entertainment",
+  "Software & Subscriptions",
+  "Hardware & Equipment",
+  "Office Supplies",
+  "Marketing",
+  "Professional Services",
+  "Utilities",
+  "Other",
+] as const;