"auto" sniffs bitmark, JSON or JSONL from the content; "bitmark" /
"json" / "jsonl" are explicit ("jsonl" is the JSON document written one
entry per line); any config mapping id (e.g. "html", "xml") selects a markup
input that is reversed to the AST. The (string & {}) arm admits those
config-driven mapping ids while keeping literal autocompletion.
Input format selector (adds auto-detection).
"auto"sniffs bitmark, JSON or JSONL from the content;"bitmark"/"json"/"jsonl"are explicit ("jsonl"is the JSON document written one entry per line); any config mapping id (e.g."html","xml") selects a markup input that is reversed to the AST. The(string & {})arm admits those config-driven mapping ids while keeping literal autocompletion.