Initial open source release

deploy/migrations/0066_system_sticker_sets_not_installed.up.sql

@@ -0,0 +1,8 @@
+-- System sticker sets are request-by-input resources for TDesktop
+-- (animated emoji, dice, generic animations). They must not be persisted as
+-- normal installed sticker packs, otherwise the client can abort/redo its
+-- installed stickers local-cache write path.
+UPDATE sticker_sets
+SET installed = false,
+    installed_date = 0
+WHERE set_kind = 'system';