Added thoughts from conversation with Chet

Author: KathleenDollard

src/System.CommandLine.Subsystems/CompletionSubsystem.cs

@@ -6,6 +6,15 @@
 
 namespace System.CommandLine;
 
+// Notes from Chet's work on static shells and further thoughts
+//    - Chet has work he can later upstream for completion script creation - static when it can be
+//    - Completions need to know - what it is, whether it is static or dynamic, and how many items would be in the list.
+//      - Not sure whether these need to be in the Completer or the trait
+//    - Validation can have many validators per type. Completions may need to have a single one.
+//    - Probably two steps - determining the available values and matching the current word
+//      - The code in CompletionContext of main/Extended to get current word requires tokens and is pretty gnarly 
+//    - File and directory are special as they can get handed off to shell ro the work
+
 public class CompletionSubsystem : CliSubsystem
 {
     public CompletionSubsystem(IAnnotationProvider? annotationProvider = null)