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/App.tsx

@@ -1,7 +1,16 @@
 import { Routes, Route, Navigate } from 'react-router-dom'
 import { Layout } from './components'
 import { AdminLayout } from './components/admin'
-import { GenlockeDetail, GenlockeList, Home, NewGenlocke, NewRun, RunList, RunEncounters, Stats } from './pages'
+import {
+  GenlockeDetail,
+  GenlockeList,
+  Home,
+  NewGenlocke,
+  NewRun,
+  RunList,
+  RunEncounters,
+  Stats,
+} from './pages'
 import {
   AdminGames,
   AdminGameDetail,
@@ -25,17 +34,26 @@ function App() {
         <Route path="genlockes/new" element={<NewGenlocke />} />
         <Route path="genlockes/:genlockeId" element={<GenlockeDetail />} />
         <Route path="stats" element={<Stats />} />
-        <Route path="runs/:runId/encounters" element={<Navigate to=".." relative="path" replace />} />
+        <Route
+          path="runs/:runId/encounters"
+          element={<Navigate to=".." relative="path" replace />}
+        />
         <Route path="admin" element={<AdminLayout />}>
           <Route index element={<Navigate to="/admin/games" replace />} />
           <Route path="games" element={<AdminGames />} />
           <Route path="games/:gameId" element={<AdminGameDetail />} />
-          <Route path="games/:gameId/routes/:routeId" element={<AdminRouteDetail />} />
+          <Route
+            path="games/:gameId/routes/:routeId"
+            element={<AdminRouteDetail />}
+          />
           <Route path="pokemon" element={<AdminPokemon />} />
           <Route path="evolutions" element={<AdminEvolutions />} />
           <Route path="runs" element={<AdminRuns />} />
           <Route path="genlockes" element={<AdminGenlockes />} />
-          <Route path="genlockes/:genlockeId" element={<AdminGenlockeDetail />} />
+          <Route
+            path="genlockes/:genlockeId"
+            element={<AdminGenlockeDetail />}
+          />
         </Route>
       </Route>
     </Routes>