[3.12] gh-96905: In IDLE code, stop redefining built-ins 'dict' and 'object' (GH-114227) (#114228)

Prefix 'dict' with 'o', 'g', or 'l' for 'object', 'global', or 'local'.
Suffix 'object' with '_'.
(cherry picked from commit 6f4b242a03e521a55f0b9e440703b424ed18ce2f)

Co-authored-by: Terry Jan Reedy <tjreedy@udel.edu>