Fix display of bindings for editor::AcceptInlineCompletion + add validation + use modifiers from keymap (#24442)

Release Notes:

- N/A

Cargo.toml

@@ -423,6 +423,7 @@ ignore = "0.4.22"
 image = "0.25.1"
 indexmap = { version = "2.7.0", features = ["serde"] }
 indoc = "2"
+inventory = "0.3.19"
 itertools = "0.14.0"
 jsonwebtoken = "9.3"
 jupyter-protocol = { version = "0.6.0" }