Fix running with tcl/tk 9

[BsAtHome]

This PR addresses and fixes #3713.

It should fix the remaining Tcl/Tk 9 problems. Tested to run axis and qtvcp on Fedora 43 (both user interfaces use the togl extension for Tcl/OpenGL view). Also compiled on Trixie and Bookworm (debian 12 and 13) in a VM and confirmed that both will run axis properly.

A few additionally found tilde expansions were addressed too. One was added via the configure script and another was still present in halshow.

Notes:

• The changes lock Tcl/Tk version to >= 8.4 as a configure check. That should be no problem because Debian has been on 8.6 since Buster (debian 11). It might even be tightened a bit.
• The compile will also lock the binary to run with the system's version of Tcl/Tk, which should be no problem because you never downgrade Tcl/Tk on a running system.
• A binary compiled for Tcl 8.6 will not work on a system with Tcl 9.0 (and vice versa). They are binary incompatible and you must recompile for the correct version.