chore: Create agents.md file

[Copilot]

This PR adapts the cursor rules file from PR #829 to the standard agents.md format, providing comprehensive guidance for AI agents working on the Apify CLI project.

Changes Made

• Created agents.md - A new file that serves as the standard AI agent instruction file for the project
• Adapted content structure - Transformed the original cursor rules (.mdc format) into a well-structured markdown document
• Enhanced documentation - Expanded the original content with additional context about project structure, development workflow, and best practices

Key Features

The new agents.md file includes:

• Project Overview - Clear description of the Apify CLI and its purpose
• Command Development Guidelines - Step-by-step instructions for creating new CLI commands
• Code Templates - Ready-to-use examples showing proper command structure
• Import Patterns - Correct usage of ApifyCommand, Args, and Flags from the command framework
• Naming Conventions - Standards for command naming (lowercase, dash-separated)
• Registration Process - How to properly add commands to apifyCommands or actorCommands arrays
• Development Workflow - Common development tasks like building, testing, and linting

Example Content

The file provides practical examples like this command template:

export class MyCommandCommand extends ApifyCommand<typeof MyCommandCommand> {
    static override name = "my-command" as const;
    
    static override description = "Description of what this command does";
    
    async run() {
        // Command logic implementation
    }
}

This maintains all the valuable guidance from the original cursor rules while making it more accessible and comprehensive for AI agents working on the codebase.

Fixes #916.

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[Copilot]

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[janbuchar]

• please make the title conform to the conventional commits spec
• at this point, the repository does not have any cursor rules - what is the PR adapting? I would instead say something like "introduce an agents.md file"

[janbuchar]

We should explain feature tests here

[janbuchar]

Let's describe this in concrete words so that the agent doesn't have to re-analyze the project every time