Add QR pairing (terminal QR, in-app scanner, iris://pair deep link)

gateway-plugin/tests/ws_probe.py

@@ -7,13 +7,13 @@ while building the Kotlin client.
 
 Usage::
 
-    hermes gateway &                      # with the android plugin
-    python gateway-plugin/tests/ws_probe.py --token <ANDROID_TOKEN> \
+    hermes gateway &                      # with the iris plugin
+    python gateway-plugin/tests/ws_probe.py --token <IRIS_TOKEN> \
         --send "hello"
 
 Options:
     --url        ws://host:port/ws   (default ws://127.0.0.1:8790/ws)
-    --token      ANDROID_TOKEN       (default: $ANDROID_TOKEN)
+    --token      IRIS_TOKEN       (default: $IRIS_TOKEN)
     --device     device_id           (default: probe-<rand>)
     --send TEXT  send this message after pairing (default: "hello")
     --upload F   M4: upload F (chunked media.upload) and attach it to the
@@ -573,7 +573,7 @@ def run_http(args, base: str) -> int:
             "v": 1,
             "id": 1,
             "type": "message.send",
-            "chat_id": "android:default",
+            "chat_id": "default",
             "payload": {"text": args.send},
         }
         conn = HTTPConnection(host, port, timeout=30)
@@ -666,8 +666,8 @@ def run_http(args, base: str) -> int:
 
 def main() -> int:
     p = argparse.ArgumentParser(description=__doc__)
-    p.add_argument("--url", default=os.getenv("ANDROID_WS_URL", "ws://127.0.0.1:8790/ws"))
-    p.add_argument("--token", default=os.getenv("ANDROID_TOKEN", ""))
+    p.add_argument("--url", default=os.getenv("IRIS_WS_URL", "ws://127.0.0.1:8790/ws"))
+    p.add_argument("--token", default=os.getenv("IRIS_TOKEN", ""))
     p.add_argument("--device", default=f"probe-{uuid.uuid4().hex[:8]}")
     p.add_argument("--send", default="hello")
     p.add_argument(
@@ -724,8 +724,8 @@ def main() -> int:
     )
     p.add_argument(
         "--chat-id",
-        default="android:default",
-        help="chat_id for --scope chat (default android:default)",
+        default="default",
+        help="chat_id for --scope chat (default default)",
     )
     p.add_argument(
         "--channel-create", default="", help="M3: create a channel, print its chat_id, exit"
@@ -762,7 +762,7 @@ def main() -> int:
     )
     args = p.parse_args()
     if not args.token and not args.authfail:
-        p.error("--token (or $ANDROID_TOKEN) is required")
+        p.error("--token (or $IRIS_TOKEN) is required")
     if args.assert_read_receipt and not args.send:
         p.error("--assert-read-receipt requires --send (the receipt must follow the sent message)")
     # HTTP is the only transport (docs/19): derive the http(s) base from the