Create Python-based interactive notebooks with marimo's reactive cell architecture.

• Notebooks are pure Python files with @app.cell decorated functions representing cells; dependencies and inputs/outputs are automatically managed through function parameters
• Supports three execution modes: script mode (non-interactive testing), interactive browser editing, and CLI execution via uv run marimo
• Use mo.app_meta().mode == "script" to detect execution context and adapt data sources without duplicating UI elements or wrapping logic in conditionals
• Built-in linting via marimo check catches common mistakes; optional pytest integration enables test cells prefixed with test_