docs: add Microsoft Store screenshots

artifacts/microsoft-store/captions.md

@@ -0,0 +1,9 @@
+# Microsoft Store screenshot order and captions
+
+1. **Review transfer** — Choose a file, name the transfer, and decide whether every receiver needs your approval.
+2. **Share with QR** — Invite another device with a QR code or a portable `.vnd` invitation file.
+3. **Transfer details** — See availability, size, access policy, receiver activity, and sharing options in one place.
+4. **Receive invitation** — Open a private VniDrop invitation to receive files directly on your PC.
+5. **Privacy and security** — Direct, account-free, end-to-end encrypted transfer with no cloud copy left behind.
+
+All final screenshots are 1920 × 1080 PNG files. The QR shown in screenshot 2 is a deliberately non-functional demo pattern; it does not contain a live transfer capability.