- feature: added mount feature for assets and mount folder

[agallardol]

Add Asset and Mount File Support for Deno Tools (docker implementation)

This PR adds support for mounting files in two ways:

• Read-only assets via context.assets
• Read-write mount files via context.mount_files

The implementation includes:

• New directories in execution storage for assets and mount points
• Docker mount configuration for file access
• Tests validating both read-only and read-write file operations

This enables tools to work with external files in a controlled manner, with clear separation between read-only assets and writable mount points.