fix: add nginx SPA fallback for BrowserRouter routing

Root cause: Docker container was 4 days old and nginx had no
try_files fallback for SPA routes like /details.

Changes:
- Add nginx.conf with try_files $uri $uri/ /index.html
- Update Dockerfile to copy nginx config
- Add production browser QA script

Production verified:
- https://arhipovdan.ru/ shows full-screen 3D demo
- https://arhipovdan.ru/details shows detailed page

scripts/test_production.py

@@ -0,0 +1,79 @@
+#!/usr/bin/env python3
+"""Test production site and take screenshots."""
+
+from playwright.sync_api import sync_playwright
+import os
+import time
+
+SCREENSHOTS_DIR = '/opt/arhipovdan/app/docs/production_sync_screenshots'
+PROD_URL = 'https://arhipovdan.ru'
+
+def main():
+    os.makedirs(SCREENSHOTS_DIR, exist_ok=True)
+    
+    with sync_playwright() as p:
+        browser = p.chromium.launch(headless=True)
+        page = browser.new_page(viewport={'width': 1920, 'height': 1080})
+        
+        console_errors = []
+        page.on('console', lambda msg: console_errors.append(msg.text) if msg.type == 'error' else None)
+        
+        print(f"1. Navigating to {PROD_URL}/")
+        page.goto(f'{PROD_URL}/')
+        page.wait_for_load_state('networkidle')
+        time.sleep(3)  # Wait for 3D to render
+        
+        print("2. Taking prod_home_after_deploy screenshot...")
+        page.screenshot(path=f'{SCREENSHOTS_DIR}/prod_home_after_deploy.png')
+        
+        # Check for key elements
+        play_button = page.locator('button.play-button')
+        details_link = page.locator('.details-link')
+        hud = page.locator('.main-hud')
+        progress_dots = page.locator('.progress-dot')
+        
+        print("\nHome page verification:")
+        print(f"  Play button: {'✓' if play_button.count() > 0 else '✗'}")
+        print(f"  Details link: {'✓' if details_link.count() > 0 else '✗'}")
+        print(f"  HUD present: {'✓' if hud.count() > 0 else '✗'}")
+        print(f"  Progress dots: {progress_dots.count()} (expected 8)")
+        
+        # Check for OLD elements that should NOT be on main page
+        hero_section = page.locator('.hero-section')
+        product_demo = page.locator('.product-demo')
+        
+        print(f"  HeroSection absent: {'✓' if hero_section.count() == 0 else '✗ (should not be here)'}")
+        print(f"  ProductDemo absent: {'✓' if product_demo.count() == 0 else '✗ (should not be here)'}")
+        
+        print(f"\n3. Navigating to {PROD_URL}/details")
+        page.goto(f'{PROD_URL}/details')
+        page.wait_for_load_state('networkidle')
+        time.sleep(2)
+        
+        print("4. Taking prod_details_after_deploy screenshot...")
+        page.screenshot(path=f'{SCREENSHOTS_DIR}/prod_details_after_deploy.png')
+        
+        # Check for details page elements
+        header = page.locator('header')
+        hero_section = page.locator('.hero-section')
+        product_demo = page.locator('.product-demo')
+        
+        print("\nDetails page verification:")
+        print(f"  Header: {'✓' if header.count() > 0 else '✗'}")
+        print(f"  HeroSection: {'✓' if hero_section.count() > 0 else '✗'}")
+        print(f"  ProductDemo: {'✓' if product_demo.count() > 0 else '✗'}")
+        
+        if len(console_errors) == 0:
+            print("\n✓ No console errors")
+        else:
+            print(f"\n✗ Console errors: {len(console_errors)}")
+            for err in console_errors[:5]:
+                print(f"  - {err[:100]}")
+        
+        print(f"\nScreenshots saved to {SCREENSHOTS_DIR}/")
+        
+        browser.close()
+        print("\nDone!")
+
+if __name__ == '__main__':
+    main()