When in regex mode, if the regex contained escapes, `serpl` writes to the files, but does not actually replace anything

Version: `serpl 0.3.4-Arch Linux (2025-05-25)` No custom config. Steps to reproduce: - Go to an empty directory. - `echo '[[foo]]' > foo` - `ls --full-time`, note the modification time - `serpl` - `Ctrl-n` to regex mode. Enter `\[\[foo\]\]` into the search box and `bar` into the replace box. - Navigate to the result list. Confirm that the `foo` file is correctly matched. - Press `r` (or `Ctrl-o` and continue) - `Ctrl-c` to quit. - `cat foo`. Notice that the file still contains `[[foo]]`. - `ls --full-time` again. Notice that the modification time has changed, indicating that `serpl` did write to the file, but didn't actually replace anything.