cmd: tab completion: Treat most delimiters as literals if user specified quotes.
Fix tab completion for commands like:
cd "[2025] Tax Documents"
while still allowing tab completion for commands like:
copy file1+file2 file3
to work.
Without this change, tab completion for cd "[2025] Tax Documents" yields cd "[2025][2025] Tax Documents". Completed text is inserted into the incorrect location due to the closing ']' which was erroneously interpreted as a delimiter before this change.