lua: Add auto-close for single quote strings and highlight escape sequences (#18199)

- Add auto close to single quote string
- Add syntax highlights to escape sequence

extensions/lua/languages/lua/config.toml

@@ -8,6 +8,6 @@ brackets = [
     { start = "[", end = "]", close = true, newline = true },
     { start = "(", end = ")", close = true, newline = true },
     { start = "\"", end = "\"", close = true, newline = false, not_in = ["string"] },
-    { start = "'", end = "'", close = false, newline = false, not_in = ["string"] },
+    { start = "'", end = "'", close = true, newline = false, not_in = ["string"] },
 ]
 collapsed_placeholder = "--[ ... ]--"

extensions/lua/languages/lua/highlights.scm

@@ -196,3 +196,4 @@
 (number) @number
 
 (string) @string
+(escape_sequence) @string.escape