README/INSTALL: link the GeuReflector (SvxReflector fork) this portal is used with

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

README.md

@@ -8,6 +8,10 @@ talkgroup requests.
 Static HTML/JS (Bootstrap from jsdelivr) plus a small PHP backend that keeps
 its data in Redis. No build step.
 
+- **Reflector:** this portal is used with [GeuReflector](https://github.com/sa2blv/GeuReflector)
+  (SA2BLV's SvxReflector fork with reflector-to-reflector trunking; upstream is
+  [audric/GeuReflector](https://github.com/audric/GeuReflector)). Its status
+  endpoint (`HTTP_SRV_PORT`) is what the live-data API is built from.
 - **Install:** see [INSTALL.md](INSTALL.md) — nginx, PHP-FPM, Redis, first admin.
 - **Config templates:** [`install/`](install/)
 - **User help:** `help.html` (served at `/help.html`)