.claude/commands/update-godocs: New command for Go doc updates

We have unit and other testing that ensures the code functions as
intended, for covered situations.  But there's not much back-pressure
to keep comments accurate or accessible.  This Claude command [1] is
mostly a reminder to ourselves that it's worth periodically reviewing
the API documentation, and if we do, it should make it easier for new
contributors to onboard themselves.  If it gets to the point that it's
detailed enough to be very helpful, we might move it to a more central
location for use in other projects, although I expect there are
already many similar slash commands out there already.

[1]: https://code.claude.com/docs/en/slash-commands

Author: wking

.claude/commands/update-godocs.md

@@ -0,0 +1,24 @@
+---
+name: update-godocs
+description: Update comments on functions, structures, and properties within a Go file.
+parameters:
+  - name: path
+    description: Path to the Go file to update.  One path at a time to make it easy to spread out review load.
+    required: true
+---
+
+You are helping users update comments on functions, structures, and properties in Go files to make it easier for new users to understand package behavior.
+
+## Context
+
+
+## Your Task
+
+Based on the user's path: "{{path}}"
+
+1. Read the Go code for that path and other Go files (with the `.go` suffix, excluding the `_test.go` suffix) in that directory to understand the package's functionality.
+2. Ensure that there is a Go file in the directory with the package-summary `// Package ...` comment.
+    If there is not yet such a file, create one, including a comment that summarizes the overall package functionality.
+3. For {{path}}, update the Go comments describing API elements to improve accuracy and clarity.
+    Prioritize public functions, structures, and properties.
+    If all public APIs already have accurate, clear comments, update comments on the file's internal APIs.