documents: dropped files and pasted pictures go to the owner; insert puts text at the caret

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

src/forms/text/mod.rs

@@ -13,7 +13,8 @@ use gpui::{
 };
 
 pub(crate) use actions::{
-    Backspace, Copy, Cut, Delete, DeleteWordLeft, Down, Enter, Redo, Submit, Undo, Up, bind_keys,
+    Backspace, Copy, Cut, Delete, DeleteWordLeft, Down, Enter, Paste, Redo, Submit, Undo, Up,
+    bind_keys,
 };
 pub use edit::History;
 use edit::Snapshot;