Add pre-commit hooks for linting and formatting

Set up pre-commit framework with ruff (backend) and ESLint/Prettier/tsc
(frontend) hooks to catch issues locally before CI. Auto-format all
frontend files with Prettier to comply with the new check.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

frontend/src/components/EndRunModal.tsx

@@ -7,7 +7,12 @@ interface EndRunModalProps {
   genlockeContext?: RunGenlockeContext | null
 }
 
-export function EndRunModal({ onConfirm, onClose, isPending, genlockeContext }: EndRunModalProps) {
+export function EndRunModal({
+  onConfirm,
+  onClose,
+  isPending,
+  genlockeContext,
+}: EndRunModalProps) {
   const victoryDescription = genlockeContext
     ? genlockeContext.isFinalLeg
       ? 'Complete the final leg of your genlocke!'