refactor: set removal version for --ts/-T flags (denoland#22039)

Towards denoland#22021

cli/args/flags.rs

@@ -1561,7 +1561,7 @@ This command has implicit access to all permissions (--allow-all).",
             .conflicts_with("ext")
             .long("ts")
             .short('T')
-            .help("deprecated: Treat eval input as TypeScript")
+            .help("deprecated: Use `--ext=ts` instead. The `--ts` and `-T` flags are deprecated and will be removed in Deno 2.0.")
             .action(ArgAction::SetTrue)
             .hide(true),
         )
@@ -3411,9 +3411,9 @@ fn eval_parse(flags: &mut Flags, matches: &mut ArgMatches) {
 
   if as_typescript {
     eprintln!(
-      "{}",
+      "⚠️ {}",
       crate::colors::yellow(
-        "Warning: --ts/-T flag is deprecated. Use --ext=ts instead."
+        "Use `--ext=ts` instead. The `--ts` and `-T` flags are deprecated and will be removed in Deno 2.0."
       ),
     );