chore: add Docker config files and fix fail2ban bind mount path

.containerignore

@@ -0,0 +1,49 @@
+# ──────────────────────────────────────────────
+#  BanGUI — .dockerignore / .containerignore
+#  Works with both Docker and Podman.
+# ──────────────────────────────────────────────
+
+# Version control
+.git
+.gitignore
+
+# Virtual environments
+.venv
+venv
+env
+
+# IDE / editor
+.vscode
+.idea
+*.swp
+*.swo
+*~
+
+# Python caches
+__pycache__
+*.pyc
+*.pyo
+.mypy_cache
+.ruff_cache
+.pytest_cache
+.coverage
+htmlcov
+
+# Node
+frontend/node_modules
+frontend/.vite
+
+# Build artifacts
+dist
+build
+*.egg-info
+
+# Documentation (keep README at root if needed)
+Docs
+
+# Tests (not needed in production images)
+backend/tests
+
+# OS files
+.DS_Store
+Thumbs.db