SEO fixes: robots.txt, canonicals, noindex, og tags, breadcrumbs, similar games, review schema

- robots.txt: proper Disallow rules + sitemap URL
- Layout: robots meta tag, fix canonical syntax, og:site_name, full Twitter Card tags
- Game pages: canonical URLs, og:type website, breadcrumb nav + JSON-LD schema
- Screenshot alt text with game title and index
- VideoGame JSON-LD: review array with rating/author/body
- Similar Games section on game detail (by genre, ordered by rating)
- browse/index: noindex on paginated or multi-filter pages
- search results: noindex + improved title
- User library and lists: noindex
- Unique meta descriptions on browse, top-rated, new-releases pages

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

resources/views/games/index.blade.php

@@ -1,6 +1,11 @@
 @extends('layouts.app')
 
 @section('title', 'Browse Games — GameLog')
+@section('description', 'Browse and discover video games. Filter by genre, platform, and year. Find your next favorite game on GameLog.')
+@section('canonical', route('games.index'))
+@if($shouldNoindex ?? false)
+@section('robots', 'noindex,follow')
+@endif
 
 @section('content')
 <div class="max-w-7xl mx-auto px-4 sm:px-6 lg:px-8 py-10">