The raw input content to preprocess
The format of the input ('yaml', 'json', or 'csv')
The preprocessed content with blocks converted, or original input if unchanged/error
// YAML bare block
preprocessCustomBlocks('desc: <<<\nText\n>>>', 'yaml');
// Returns: 'desc: "Text"'
// JSON with quotes inside
preprocessCustomBlocks('{"a": <<<\nSay "hi"\n>>>}', 'json');
// Returns: '{"a": "Say \\"hi\\""}'
// CSV cell
preprocessCustomBlocks('A,B\n1,<<<\nLine 1\n>>>', 'csv');
// Returns: 'A,B\n1,"Line 1"'
Preprocess custom blocks in input content.
Converts
<<<\n...content...\n>>>blocks into properly quoted strings with format-specific escaping. Handles both bare and quoted blocks.