bug#68160: 29.1; Windows installer: add Emacs bin directory to PATH

[Michael Hoffman]

Could the Windows installer add $INSTDIR\emacs-${VERSION_BRANCH}\bin to
PATH?

I've started installing Emacs on Windows via WinGet, which is very nice,
and so much works out of the box, but Emacs commands are not added to
PATH like they are with Chocolatey. Currently, WinGet does not support
adding to PATH for packages with an installer, like Emacs.

If not, would it be possible to add an option to the installer to do
this? A WinGet package could include that as a custom installer option
<https://github.com/microsoft/winget-pkgs/blob/master/doc/manifest/schema/1.5.0/installer.md>.

In GNU Emacs 29.1 (build 2, x86_64-w64-mingw32) of 2023-08-02 built on
 AVALON
Windowing system distributor 'Microsoft Corp.', version 10.0.19045
System Description: Microsoft Windows 10 Home (v10.0.2009.19045.3803)

Configured using:
 'configure --with-modules --without-dbus --with-native-compilation=aot
 --without-compress-install --with-tree-sitter CFLAGS=-O2'

Configured features:
ACL GIF GMP GNUTLS HARFBUZZ JPEG JSON LCMS2 LIBXML2 MODULES NATIVE_COMP
NOTIFY W32NOTIFY PDUMPER PNG RSVG SOUND SQLITE3 THREADS TIFF
TOOLKIT_SCROLL_BARS TREE_SITTER WEBP XPM ZLIB

(NATIVE_COMP present but libgccjit not available)

Important settings:
  value of $LANG: en_US
  locale-coding-system: utf-8-unix

Major mode: Special