docs: Add A2A_QueryTask documentation and update configuration

[edenreich]

Adds comprehensive documentation for the A2A_QueryTask tool including usage examples and important notes about when to use it. Updates the A2A tool configuration section with complete configuration options and clarifies the relationship between task submission and querying.

Summary of Changes

1. Added detailed documentation for the A2A_QueryTask tool:

   • Usage examples showing how to query task status
   • Important notes about when to use QueryTask vs. automatic monitoring
   • Clear guidance on proper usage patterns

2. Updated A2A tool configuration section:

   • Added complete configuration options for all A2A tools
   • Clarified the relationship between task submission and querying
   • Removed outdated shortcut command section

3. Tool implementation details:

   • Added comprehensive documentation for QueryTask parameters
   • Improved overall documentation structure and clarity

Why This Matters

• Provides clear guidance for developers using A2A tools
• Prevents misuse of QueryTask by clarifying when it should be used
• Updates documentation to reflect current tool capabilities
• Improves developer experience with better examples and explanations

[edenreich]

Update: This PR now also includes restoration and enhancement of the /a2a shortcut documentation that was accidentally removed in a previous commit.

Additional Changes

The /a2a shortcut documentation has been fully restored and enhanced:

Restored /a2a Shortcut Documentation

• Complete documentation for /a2a list, /a2a add, and /a2a remove commands
• Clear distinction between /a2a shortcut (configuration management) and A2A tools (runtime interaction)
• Practical examples showing agent configuration workflow
• All available options documented for /a2a add command

Key Clarification

The /a2a shortcut is NOT outdated - it serves a complementary purpose to the A2A tools:

• /a2a shortcut: Configuration management (add/remove/list agents)
• A2A Tools: Runtime interaction (submit tasks, query agents, download artifacts)

Both systems work together: use /a2a to configure agents, then use A2A tools to interact with them.

[ig-semantic-release-bot]

🎉 This PR is included in version 0.76.3 🎉

The release is available on GitHub release

Your semantic-release bot 📦🚀