security-dashboard: drop the port from Sipnetic QR's TURN server field

Sipnetic's own documented "st" field format is explicit that the value is a
hostname/IP without a port -- its worked example (turn:user:pass@host) has
no port anywhere, even in the URI-with-credentials form. Appending :3478 as
this repo was doing gets silently truncated by the app: confirmed live, the
FQDN came through on scan but the port after it did not.

coturn's listening port in this repo is always the STUN/TURN-conventional
3478 anyway, which is what a portless address implies, so stripping it
before building the st field costs nothing and matches the actual spec.

services/security-dashboard.sh

@@ -3041,17 +3041,25 @@ def ea_device_sipnetic_string(extension):
     IS a verified, documented format for one specific app, built from the
     exact same ea_device_details() data.
 
-    st is intentionally set to an explicit turn:user:pass@host:port URI
+    st is intentionally set to an explicit turn:user:pass@host URI whenever
-    (Sipnetic's doc confirms the st field accepts embedded credentials in
+    coturn is configured, rather than left unset -- leaving it out doesn't
-    that form) whenever coturn is configured, rather than left unset --
+    mean "no TURN", it means Sipnetic falls back to its own default/built-in
-    leaving it out doesn't mean "no TURN", it means Sipnetic falls back to
+    STUN server instead of the coturn instance Asterisk itself is actually
-    its own default/built-in STUN server instead of the coturn instance
+    using, which is silently wrong rather than absent. This is the same
-    Asterisk itself is actually using, which is silently wrong rather than
+    TURN_SERVER/TURN_USERNAME/TURN_PASSWORD ea_device_details() already
-    absent. This is the same TURN_SERVER/TURN_USERNAME/TURN_PASSWORD
+    reads from the Asterisk .env (see ea_connection_defaults()) -- whichever
-    ea_device_details() already reads from the Asterisk .env (see
+    coturn Asterisk is actually configured against.
-    ea_connection_defaults()) -- whichever coturn Asterisk was configured
+
-    against (the shared instance on a droplet, or an embedded one), not a
+    The host is deliberately stripped of its port before going into st.
-    second, separately-derived value.
+    Sipnetic's own doc for this field is explicit that the value is a
+    "hostname or IP address without port", and its own worked example is
+    `st=turn:user:password@turn.mydomain.com;` -- no port anywhere, even
+    in the URI form. Confirmed live: appending :3478 (matching the doc's
+    generic URI-with-credentials description, which doesn't actually show a
+    port example) gets silently truncated by the app -- the FQDN came
+    through, the port after it did not. coturn's listening port in this
+    repo is always the STUN/TURN-conventional 3478, which is what a
+    portless address implies anyway, so dropping it costs nothing.
 
     A literal ';' in any field must be doubled per that same doc page --
     generated passwords are alnum-only (_ea_generate_password) so this only
@@ -3073,8 +3081,9 @@ def ea_device_sipnetic_string(extension):
         "dt=%s" % dt,
     ]
     if d.get("turn_server") and d.get("turn_username") and d.get("turn_password"):
+        turn_host = d["turn_server"].rsplit(":", 1)[0]
         fields.append("st=%s" % esc_field(
-            "turn:%s:%s@%s" % (d["turn_username"], d["turn_password"], d["turn_server"])
+            "turn:%s:%s@%s" % (d["turn_username"], d["turn_password"], turn_host)
         ))
     return ";".join(fields) + ";"