[paul-v-snet]

Description

Inherits #407, based on OMEGA-431 proposed approach.
This PR implements a new core skill: custom-skill-management for custom skills creation, deletion and editing.

As that has been proposed in OMEGA-431, this core skill is placed at plugins/workflow/instructions, but created custom skills will be placed at memory/workflow/skills and will survive Omega updates and/or container recreation since they will be part of the omega-memory volume.

Implemented behavior:

• To trigger the skill, it's enough to send a message in the chat like create a new custom skill for <task>
• The skill does not allow editing, removing or renaming any core skill
• The skill allows only names that comply with the official common specification
• The skill always calls the workflow-refresh-list expression as a mandatory last step so newly created custom skills will be available immediately after creation

How Has This Been Tested?

Ran the live agent, tested many scenarios, including:

• Create a new custom skill: passed
• Edit a previously created custom skill: passed
• Delete a custom skill: passed
• Attempt to name a newly created custom skill with an invalid name such as x;3, rm -rf ~/', --skill-name` and so on: all attempts were blocked, passed
• Attempt to edit/rename a core skill: was blocked, passed

The memory-export mechanism has also been tested: skills as well as all options worked fine - all data was exported/imported successfully.

Checklist

• PR contains autogenerated code
  • SKILL.md was improved iteratively with help of an AI-assistant
• Self-review completed
• Test scenarios above are passed with the version of the code from PR