Refactor EOL components, add CI test suite and nightly image build

[neonspectra]

Upgraded the backend to Laravel 12 (from Laravel 5.6) and PHP 8.4 (from PHP 7.4), modernized the bootstrap/routing/middleware setup, and updated the test harness to be PHPUnit 11‑compatible with an auto‑generated SQLite test DB.

Upgraded the frontend stack to Vue 3 (Vue 2 is EOL), Vue Router 4, Vuex 4, and Laravel Mix 6 / Webpack 5, plus moved the build stage to Node 24 LTS.

Documented the new build and test steps and updated env handling for VITE_GOOGLE_ANALYTICS_ID (backward‑compatible with MIX_).

Updated test suite with new frontend and character sheet export smoke tests, documented in tests/README.md. Added CI to run these on new commits.

Key changes

• Backend: bootstrap/app.php, public/index.php, artisan, app/Providers/RouteServiceProvider.php, app/Http/Middleware/TrustProxies.php, app/Exceptions/Handler.php, routes/*.php, composer.json, composer.lock, phpunit.xml, `tests/*.
• Frontend: package.json, package-lock.json, webpack.mix.js, resources/js/app.js, resources/sass/vendor.scss, resources/views/, main.blade.php.
• Docker/runtime: Dockerfile now uses Node 24 and PHP 8.4; includes required PHP extensions.

Tests run

• sudo docker build -t epcc .
• sudo docker run --rm -d -p 8080:80 --name epcc_test epcc
• curl -fsS http://localhost:8080/ | head -n 5
• `sudo docker inspect --format='{{json .State.Health}}' epcc_test
• sudo docker run --rm -v "$PWD":/app -w /app composer:2 sh -lc "git config --global --add safe.directory /app && composer install && vendor/bin/phpunit"

Notes

• PHPUnit now passes; still reports two deprecations (from the upgraded framework/tooling), but no failing tests.
• Docker image health check reaches healthy after the first interval.

[darvell]

@copilot review and fix CI