Add user registration and auth web app

FastAPI + Jinja2 + MariaDB web application with registration,
login, profile, password reset, and email confirmation flows.
All UI in Russian. Styled with Evotor brand colors.

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

.env.example

@@ -0,0 +1,8 @@
+DATABASE_URL=mysql+pymysql://evosync:evosync@db:3306/evosync
+SECRET_KEY=your-random-secret-key-here
+BASE_URL=http://localhost:8000
+
+DB_ROOT_PASSWORD=rootpass
+DB_NAME=evosync
+DB_USER=evosync
+DB_PASSWORD=evosync