Fix CLI group create command to require all mandatory fields

[Copilot]

Problem

The CLI group create command was not enforcing all required fields at the command line level, allowing users to create event receiver groups without providing mandatory parameters. This could lead to confusing error messages from the backend validation rather than clear upfront validation.

According to the issue requirements, all Event Receiver Groups must have these required fields:

• name: String!
• type: String!
• version: String!
• description: String!
• enabled: Boolean!
• event_receiver_ids: [ID!]!

Changes

Updated cli/cmd/group/create.go to mark version and enabled flags as required, matching the backend validation requirements.

Before:

$ epr-cli group create --name "test" --type "test.type" --description "test desc" --event-receiver-ids "id1"
# Would attempt to send request to backend and fail with backend validation error

After:

$ epr-cli group create --name "test" --type "test.type" --description "test desc" --event-receiver-ids "id1"
Error: required flag(s) "enabled", "version" not set

Testing

• ✅ CLI now properly validates all required fields are provided
• ✅ Works correctly with both --enabled=true and --enabled=false
• ✅ All existing tests continue to pass
• ✅ Backend validation remains unchanged and functional

The fix ensures users get immediate, clear feedback about missing required parameters rather than cryptic backend errors.

Original prompt

---

This section details on the original issue you should resolve

<issue_title>CLI is able to create a event receiver group without a type</issue_title>
<issue_description>Need to make sure we are requiring all appropriate fields for create mutations in graphql

Require the following fields for event group receivers:

name: String!
type: String!
version: String!
description: String!
enabled: Boolean!
event_receiver_ids: [ID!]!

https://github.com/sassoftware/event-provenance-registry/blob/main/cli/cmd/group/create.go </issue_description>

<agent_instructions>Update the create command for groups to require all specified fields for an Event Receiver Group</agent_instructions>

Comments on the Issue (you are @copilot in this section)

Fixes #96

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[gbuskey]

insane PR description for a one line change