docs: rewrite README for the TextCommandCallingArgs API

README.md

@@ -16,7 +16,7 @@ Add it as a dependency in your `modinfo.json`:
 ```json
 "dependencies": {
     "game": "1.22.3",
-    "commandhook": "1.0.0"
+    "commandhook": "2.0.0"
 }
 ```
 
@@ -31,16 +31,24 @@ A listener provides:
 - `Commands`, the command names you want to watch, without the leading slash
 - `Registration`, a `Before` delegate, an `After` delegate, or both
 
-`Before` runs before the command executes. Set `data.Cancel = true` inside it
-to stop the command from running. If you cancel, any remaining `Before`
-listeners for that command are skipped, and `After` never fires for that
-invocation.
+`Before` receives the engine's own `TextCommandCallingArgs` for the
+invocation, live and unmodified. Return a non-null `TextCommandResult` to
+cancel the command and report that result to the caller, use the engine's
+own factories, e.g. `TextCommandResult.Error(...)` for a visible reason, or
+`TextCommandResult.Deferred` to cancel silently (per its own doc comment,
+this prints no output). Return `null` to let the command run normally. If
+you cancel, any remaining `Before` listeners for that command are skipped,
+and `After` never fires for that invocation.
 
-`After` runs once the command has produced a result. It only fires on the
-path where the command actually ran.
+`After` receives the same `TextCommandCallingArgs` object plus the
+`TextCommandResult` the command actually produced. It only fires on the
+path where the command ran.
 
-`CommandData` is passed by `ref` the whole way through, no allocation per
-command.
+### A note on `TextCommandCallingArgs` at Before vs After
+
+This is the engine's own live object, not a copy, what's safe to read
+depends on timing and on how the specific command you're watching is
+implemented internally.
 
 ### Example
 
@@ -56,23 +64,26 @@ public class MyListener : ICommandHookListener
     // Wire up Before, After, or both.
     public CommandRegistration Registration => new(Before, After);
 
-    private void Before(ref CommandData data)
+    private TextCommandResult? Before(TextCommandCallingArgs args)
     {
-        // data.Sender is null for console invocations.
-        if (data.Sender != null && !IsAllowed(data.Sender))
+        // args.Caller.Player is null for console invocations.
+        if (args.Caller.Player is IServerPlayer player && !IsAllowed(player))
         {
-            // Stops the command from running and skips any remaining
-            // Before listeners. After never fires for this invocation.
-            data.Cancel = true;
+            // Cancels the command, skips any remaining Before listeners,
+            // and After never fires for this invocation. The caller sees
+            // this exact result.
+            return TextCommandResult.Error("You're not allowed to do that", "notallowed");
         }
+
+        return null;
     }
 
-    private void After(ref CommandData data, TextCommandResult result)
+    private void After(TextCommandCallingArgs args, TextCommandResult result)
     {
         // Only runs if nothing cancelled. result is whatever the command
         // actually produced, check result.Status for success/error/deferred.
         if (result.Status != EnumCommandStatus.Success)
-            Logger.Warn($"/{data.CommandName} failed: {result.StatusMessage}");
+            Logger.Warn($"A watched command failed: {result.StatusMessage}");
     }
 }
 ```