added init files

.gitignore

@@ -0,0 +1,22 @@
+# Haupt .gitignore im Projekt-Root
+backend/node_modules/
+frontend/node_modules/
+backend/database/*.db
+backend/database/*.db-journal
+backend/dist/
+frontend/build/
+.env
+.env.local
+.env.development.local
+.env.test.local
+.env.production.local
+*.log
+npm-debug.log*
+yarn-debug.log*
+yarn-error.log*
+.DS_Store
+Thumbs.db
+.idea/
+.vscode/
+*.tgz
+*.tar.gz