fix: namespace rate limit buckets per endpoint, remove custom analytics

- Add `prefix` param to checkRateLimit/getRateLimitHeaders so each endpoint
  has its own bucket (previously all shared `admin_${ip}`, causing 429s when
  analytics/track incremented past n8n endpoints' lower limits)
- n8n/hardcover/currently-reading → prefix 'n8n-reading'
- n8n/status → prefix 'n8n-status'
- analytics/track → prefix 'analytics-track'
- Remove custom analytics system (AnalyticsProvider, lib/analytics,
  lib/useWebVitals, all /api/analytics/* routes) — was causing 500s in
  production due to missing PostgreSQL PageView table
- Remove analytics consent toggle from ConsentBanner/ConsentProvider

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

app/projects/[slug]/page.tsx

@@ -41,25 +41,6 @@ const ProjectDetail = () => {
             const loadedProject = data.projects[0];
             setProject(loadedProject);
             
-            // Track page view
-            try {
-              await fetch('/api/analytics/track', {
-                method: 'POST',
-                headers: {
-                  'Content-Type': 'application/json',
-                },
-                body: JSON.stringify({
-                  type: 'pageview',
-                  projectId: loadedProject.id.toString(),
-                  page: `/projects/${slug}`
-                })
-              });
-            } catch (trackError) {
-              // Silently fail tracking
-              if (process.env.NODE_ENV === 'development') {
-                console.error('Error tracking page view:', trackError);
-              }
-            }
           }
         }
       } catch (error) {