feat: implement comprehensive reading analytics system with bot detection

Features:
- Add article view tracking with automatic deduplication (per user/IP)
- Implement intelligent bot detection (35+ patterns: Google, Bing, Baidu, GPTBot, etc)
- Create admin analytics dashboard with statistics and filtering
- Display view count and comment count on article cards
- Add search-based article filter (replaced dropdown for scalability)

Analytics Dashboard:
- Global stats: total views, human/bot views, unique IPs/users
- Top 20 articles ranking with detailed metrics
- Detailed view records with time, article, user, IP, user-agent
- Filters: article title search, IP search, show/hide bots
- Pagination support (50 records per page)

Technical Implementation:
- Async view recording (non-blocking)
- Dual deduplication (application + database layer)
- Database indexes for performance optimization
- Batch query for comment counts
- Full i18n support (Chinese/English)

Files Added:
- models/article_view.go: View tracking model
- models/bot_detector.go: Bot detection logic
- handlers/admin_analytics.go: Analytics page handler
- templates/admin/analytics_views.html: Analytics UI
- test_analytics.sh: Testing script
- Documentation: implementation guide, usage guide, changelog

Files Modified:
- handlers/home.go: Add view recording and comment count queries
- models/db.go: Add ArticleView to auto-migration
- main.go: Add analytics routes
- i18n/i18n.go: Add 35+ translation keys
- templates/admin/dashboard.html: Add analytics entry link
- templates/pages/home.html: Display view/comment counts on cards

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

templates/admin/dashboard.html

@@ -63,6 +63,10 @@
                 class="inline-flex items-center gap-2 bg-gray-200 text-gray-700 px-6 py-3 rounded-lg font-medium hover:bg-gray-300 transition-colors">
                 {{index .Tr "settings_nav"}}
             </a>
+            <a href="/admin/analytics/views"
+                class="inline-flex items-center gap-2 bg-gray-200 text-gray-700 px-6 py-3 rounded-lg font-medium hover:bg-gray-300 transition-colors">
+                {{index .Tr "analytics_views_title"}}
+            </a>
             {{end}}
         </div>
     </div>