Numbers proceeded with the escape character ignored fix (#15684)

Fixes #15675

I've added relevant test cases to ensure coverage of the identified bug.
The issue originated from my crate and pertains to the bracoxide
dependency—a bug I’ve internally referred to as IgnorantNumbers. I’ve
submitted a fix and updated the bracoxide dependency accordingly.

crates/nu-command/src/strings/str_/expand.rs

@@ -376,6 +376,20 @@ mod tests {
         );
     }
 
+    #[test]
+    fn test_numbers_proceeding_escape_char_not_ignored() {
+        assert_eq!(
+            str_expand("1\\\\{a,b}", Span::test_data(), Span::test_data()),
+            Value::list(
+                vec![
+                    Value::string(String::from("1\\a"), Span::test_data(),),
+                    Value::string(String::from("1\\b"), Span::test_data(),)
+                ],
+                Span::test_data(),
+            )
+        );
+    }
+
     #[test]
     fn test_examples() {
         use crate::test_examples;