0e09eaf43b
Embedded Python ships with tcl8.6/ and tk8.6/ next to python.exe, but Tcl's auto-detection searches <exe>/../lib/tcl8.6 — a path that doesn't exist in our layout. Without these env vars, tkinter.Tk() raises "Can't find a usable init.tcl", breaking the screen overlay (and any other tk-based UI) on installed builds.