Automate SAM download and fix database path issues

- Fix database path mismatch: download_sample_eyes.py now uses
  ai_photo_edit.db instead of photoedit.db
- Add init_database.py script to initialize DB before eye import
- Add AUTO_DOWNLOAD_SAM=true environment variable (default: enabled)
- Update entrypoint.sh to:
  1. Initialize database first
  2. Auto-download SAM model (~375MB) on first startup
  3. Then import eyes (now works since DB exists)
- Update path detection to work in both Docker and local environments

.env.example

@@ -116,7 +116,12 @@ SECRET_KEY=change-this-to-a-long-random-string-in-production
 CORS_ORIGINS=http://localhost:5173,http://localhost:3000,http://localhost:3080,http://localhost
 
 # Database path
-DATABASE_URL=sqlite:///./data/photoedit.db
+DATABASE_URL=sqlite:///./data/ai_photo_edit.db
+
+# Auto-download SAM model on startup (true/false)
+# When true (default): Downloads SAM model (~375MB) on first startup for offline Smart Select
+# When false: Skips download, Smart Select uses Replicate API (requires REPLICATE_API_KEY)
+AUTO_DOWNLOAD_SAM=true
 
 # Allow users to select model per-edit
 ALLOW_MODEL_OVERRIDE=true