graphics/vnc/server breakage

When the VNC server was created initially, it worked well. However, in 2019 as part of the Twm4Nx development, I tried to use it and it did not work. These are problems that I noted:

* Mouse Input is not received and, hence, the cursor is not drawn. Twn4Nx is not useful with not mouse cursor.
* Background is black (it should be blue @16bpp). Colors are bad. Background is not transparent. Toolbar buttons are visible but no other part of the Window.
* I think that root cause of the drawing errors is the RRE is not working. Or, more likely, it has been deprecated and no longer supported by the host VNC client.
* There are other Twm4Nx/VNC server integration issues but these do not seem to be directly related to VNC server issues.

I did make several changes in graphics/vnc/server but did not fix the basic problems.

Start by reading graphics/vnc/server and reproduce the reported behavior with Twm4Nx and a host VNC client. Investigate mouse input, cursor rendering, background and color display, transparency, toolbar visibility, and RRE support. Done means the VNC server renders the window correctly and accepts mouse input.

Written by the indexing model from the issue text.