Function parse_range 

pub fn parse_range(input: &str) -> Result<(DateTime<Local>, DateTime<Local>)>

Parse a date range expression into a (start, end) tuple of DateTime<Local>.

Supports range separators: to, through, thru, until, til, and --/-. Each side of the range is parsed as a natural language date expression via chronify.

When given a single date (no range separator), returns a 24-hour span from the start of that day to start of the next day.

Examples

• "monday to friday"
• "yesterday to today"
• "2024-01-01 through 2024-01-31"
• "last monday to next friday"
• "yesterday" (returns yesterday 00:00:00 to today 00:00:00)
• "2024-01-15" (returns 2024-01-15 00:00:00 to 2024-01-16 00:00:00)