Add cockpit deployment package + single-instance guard

deploy/ builds a single zip for TeslaConsole: the self-contained tray app and
the signed ViGEmBus installer under a riojoy\ folder, with postinstall.bat at the
root. postinstall elevates and runs riojoy\install-rio.ps1, which installs
ViGEmBus silently (if absent) and registers RIOJoy to start at logon — no cert
trust, test signing, Secure Boot change, or reboot.

Also guard against two instances fighting over the COM port (machine-wide +
per-user autostart both firing): a per-session named mutex makes a second launch
exit immediately. Built zips (dist/) and the bundled installer (deploy/vendor/)
are git-ignored.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

.gitignore

@@ -3,6 +3,10 @@
 ##
 ## Get latest from https://github.com/github/gitignore/blob/master/VisualStudio.gitignore
 
+# RIOJoy deployment: built zips and bundled third-party installers (not source).
+/dist/
+/deploy/vendor/
+
 # User-specific files
 *.rsuser
 *.suo