Digit Start Permutations

You are given a string s made of lowercase letters and digits. Return every distinct rearrangement of all the characters of s whose first character is a digit.

• Each result uses every character of s exactly once.
• Characters may repeat in s; rearrangements that produce the same string are listed once.
• Return the strings sorted in ascending order (normal string comparison, where digits come before letters).
• If s contains no digit, return an empty list.