QuiltSync README: lead with the vision (tagline + prologue) (#780)

Author: fiskus

quilt-sync/README.md

@@ -1,9 +1,24 @@
-# QuiltSync
+# Cross-platform desktop application for editing Quilt data packages
 
-## Cross-platform desktop application for editing Quilt data packages
+**QuiltSync keeps your data under revision control and never asks you to
+think about it.**
 
-Uses Tauri (<https://tauri.app/v1/guides/getting-started/setup/html-css-js>)
-to build a Rust application with a web frontend.
+Built for bench scientists rather than engineers, QuiltSync lets you find a
+data package in the Quilt Web Catalog, open it on your desktop, and bring
+down only the files you need — not the whole package — into an ordinary
+local folder.
+
+Edit them in your usual tools and QuiltSync syncs your changes back as a new
+revision, so getting data in and out never means the command line or
+uploading file copies through the browser.
+
+Every revision is an immutable, reproducible snapshot with its metadata —
+versioned data you can trust and return to, not the opaque mirroring of
+ordinary file-sync.
+
+Your team's existing rules still apply: each revision conforms to the
+workflow configured for its bucket and reuses the same roles and policies
+you already have in the Catalog — nothing new to set up.
 
 ## Usage