stays: note Booking.com reply channel

sources/stays/2026-09-16_YosemiteCabin_Booking_Chat.md

@@ -80,7 +80,7 @@ The original messages are from the host; the guest reply is recorded below.
 >
 > The Yosemite Grand Team
 
-**Guest reply — Sep 19, 2026 — sent**
+**Guest reply via Booking.com — Sep 19, 2026 — sent**
 
 > Dear Yosemite Grand Team,
 >
@@ -103,5 +103,6 @@ Notes
 - The Sep 14 message links to a password-protected welcome page
   (passcode 6333). Contents saved in `2026-09-14_Yosemite_Welcome_Packet.md`.
 - The host's request to confirm receipt of the welcome information and give an
-  estimated arrival time was answered by the guest on Sep 19, 2026.
+  estimated arrival time was answered by the guest via Booking.com on Sep 19,
+  2026.
 - Fastest contact per host: text +1 209-347-6333.