No cursor after exiting vim

### Windows Terminal version (or Windows build number)

1.8.1521.0

### Other Software

vim 7.4.576 (via SSH inside WSL)
````
linux-vdso.so.1 (0x00007ffffd7f6000)
libm.so.6 => /lib/x86_64-linux-gnu/libm.so.6 (0x00007f151d9c1000)
libtinfo.so.5 => /lib/x86_64-linux-gnu/libtinfo.so.5 (0x00007f151d797000)
libselinux.so.1 => /lib/x86_64-linux-gnu/libselinux.so.1 (0x00007f151d572000)
libacl.so.1 => /lib/x86_64-linux-gnu/libacl.so.1 (0x00007f151d369000)
libgpm.so.2 => /usr/lib/x86_64-linux-gnu/libgpm.so.2 (0x00007f151d163000)
libdl.so.2 => /lib/x86_64-linux-gnu/libdl.so.2 (0x00007f151cf5f000)
libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007f151cbb4000)
libpcre.so.3 => /lib/x86_64-linux-gnu/libpcre.so.3 (0x00007f151c946000)
/lib64/ld-linux-x86-64.so.2 (0x00007f151e0ef000)
libattr.so.1 => /lib/x86_64-linux-gnu/libattr.so.1 (0x00007f151c741000)
libpthread.so.0 => /lib/x86_64-linux-gnu/libpthread.so.0 (0x00007f151c524000)
````

### Steps to reproduce

A few times start vim, switch the window and wait...

### Expected Behavior

Everytime a flashing cursor after switching back.

### Actual Behavior

Sometimes the cursor disappears, reset(1) helps.

Start by reproducing the missing-cursor behavior with Vim 7.4.576 over SSH inside WSL in Windows Terminal 1.8.1521.0, switching away and back repeatedly. Investigate the terminal behavior around window switching and cursor restoration; done means the cursor reliably reappears without needing reset(1).

Written by the indexing model from the issue text.