feat: Add photo management features, duplicate detection, attempt limits, and admin deletion

- Add duplicate photo detection (file hash and URL checking)
- Add max attempts per photo with UI counter
- Simplify penalty system (auto-enable when points > 0)
- Prevent scores from going below 0
- Add admin photo deletion functionality
- Improve navigation with always-visible logout
- Prevent users from guessing their own photos

jest.config.js

@@ -0,0 +1,40 @@
+// eslint-disable-next-line @typescript-eslint/no-require-imports
+const nextJest = require('next/jest')
+
+const createJestConfig = nextJest({
+  // Provide the path to your Next.js app to load next.config.js and .env files in your test environment
+  dir: './',
+})
+
+// Add any custom config to be passed to Jest
+const customJestConfig = {
+  setupFilesAfterEnv: ['<rootDir>/jest.setup.js'],
+  testEnvironment: 'jest-environment-jsdom',
+  moduleNameMapper: {
+    '^@/(.*)$': '<rootDir>/$1',
+  },
+  testMatch: [
+    '**/__tests__/**/*.[jt]s?(x)',
+    '**/?(*.)+(spec|test).[jt]s?(x)',
+  ],
+  collectCoverageFrom: [
+    'app/**/*.{js,jsx,ts,tsx}',
+    'components/**/*.{js,jsx,ts,tsx}',
+    'lib/**/*.{js,jsx,ts,tsx}',
+    '!**/*.d.ts',
+    '!**/node_modules/**',
+    '!**/.next/**',
+  ],
+  // Coverage threshold disabled for now - will be enabled as test coverage increases
+  // coverageThreshold: {
+  //   global: {
+  //     branches: 50,
+  //     functions: 50,
+  //     lines: 50,
+  //     statements: 50,
+  //   },
+  // },
+}
+
+// createJestConfig is exported this way to ensure that next/jest can load the Next.js config which is async
+module.exports = createJestConfig(customJestConfig)