Agent Definition Fix

Issue Description

The Gemini CLI reported errors when loading several agent definition files in ~/.gemini/agents/. The errors are:

1. Unrecognized key(s) in object: 'color': The color property in the frontmatter is not supported.
2. tools: Expected array, received string: The tools property is defined as a comma-separated string but must be a list.

Objective

Fix the agent definition files by removing the unsupported color property and converting the tools property to a list format where necessary.

Scope

All .md files in ~/.gemini/agents/.