T5DE's local proxy for IMVU Classic

The client sends it every HTTP request and its IMQ connection; it makes them with current TLS and
certificates, upgrades IMVU's plain-HTTP hosts to HTTPS, and refuses IMVU's reporting endpoints. CI
tests it and publishes t5de-proxy.exe as nightlies and tagged releases.

Co-Authored-By: Claude Opus 5.5 <[email protected]>

internal/parent/parent.go

@@ -0,0 +1,7 @@
+// Package parent watches the process that started the proxy, so the proxy exits with it.
+package parent
+
+// Wait returns once the process pid has exited (at once if it already has, or can't be watched).
+func Wait(pid int) error {
+	return wait(pid)
+}