Function format 

pub fn format(source: &str, options: &FormatOptions) -> String

Format Snowflake SQL source text. Never panics; never drops content.

Phase 3 scope: we only reflow input the lexer and parser fully accept. If lexing or parsing reports any error (i.e. the grammar does not yet model some construct, or a token is unterminated), the source is returned unchanged — trivially lossless and idempotent — rather than risking a mangled reflow of a fragmented tree.