Add BackgroundImage model and enhance card templates with dynamic backgrounds

.gitignore

@@ -0,0 +1,58 @@
+# OS
+.DS_Store
+Thumbs.db
+desktop.ini
+$RECYCLE.BIN/
+
+# Logs
+logs/
+*.log
+npm-debug.log*
+yarn-debug.log*
+yarn-error.log*
+.pnpm-debug.log
+
+# Node
+node_modules/
+dist/
+build/
+out/
+coverage/
+.nyc_output/
+
+# Environment
+.env
+.env.*.local
+
+# IDEs and editors
+.vscode/
+.idea/
+*.sublime-workspace
+*.sublime-project
+*.code-workspace
+
+# Package managers
+package-lock.json
+.pnpm-store/
+# (keep yarn.lock if you rely on it; remove above line to keep package-lock.json in repo)
+
+# Python
+__pycache__/
+*.py[cod]
+venv/
+ENV/
+env/
+
+# Java / JVM
+target/
+*.class
+*.jar
+*.war
+*.ear
+*.iml
+
+# Misc
+*.sqlite
+*.db
+*.swp
+*~