[docs] cli node commands

[neotheprogramist]

Description

This PR adds comprehensive documentation for the partner-chains-node-commands crate, which provides the CLI interface for Partner Chains node operations. The documentation package includes:

Changes Made

1. Enhanced src/lib.rs with complete API documentation

• Added comprehensive module-level documentation explaining architecture and usage patterns
• Documented all public command structs (AriadneParametersCmd, SidechainParamsCmd, RegistrationStatusCmd)
• Added detailed documentation for the PartnerChainsSubcommand enum with all 8 command variants
• Thoroughly documented the main run function with type parameters, arguments, and usage examples
• Enhanced helper functions (setup_log4rs, print_result) with comprehensive documentation
• Improved test documentation

2. Created comprehensive README.md

• Overview of Partner Chains and CLI functionality
• Detailed descriptions of all core commands with practical usage examples
• Architecture explanation covering command structure and generic design
• Dependencies documentation (core, Partner Chains specific, cryptography)
• Error handling patterns and logging configuration
• Development guidelines including building, testing, and integration
• Security considerations and contributing guidelines

3. Added SUMMARY.md documentation index

• Documentation overview and file descriptions
• Quality checklist and maintenance guidelines
• Target audience breakdown (node operators, validators, developers, smart contract developers)
• Integration information with broader Partner Chains ecosystem

Documentation Quality

• ✅ All public APIs documented with practical examples
• ✅ Command usage examples with real-world scenarios
• ✅ Error cases and edge conditions covered
• ✅ Type parameters and generic constraints explained
• ✅ Integration patterns for different user types
• ✅ Maintenance and contribution guidelines

This documentation serves multiple audiences:

• Node Operators: Command usage and troubleshooting guides
• Validators: Registration and committee participation procedures
• Developers: API integration and extension guidelines
• Smart Contract Developers: Contract interaction patterns

The documentation follows Rust best practices with rustdoc conventions and provides comprehensive coverage suitable for both end-users and developers integrating with the Partner Chains ecosystem.

Checklist

• Commit sequence broadly makes sense and commits have useful messages.
• The size limit of 400 LOC isn't needlessly exceeded (documentation additions)
• The PR refers to a JIRA ticket (if one exists)
• New tests are added if needed and existing tests are updated. (N/A - documentation only)
• New code is documented and existing documentation is updated.
• Relevant logging and metrics added (N/A - documentation only)
• Any changes are noted in the changelog.md for affected crate
• Self-reviewed the diff

Notes

• No functional code changes were made, only documentation additions and enhancements
• No new tests required as this is purely documentation work
• The existing test in the module was enhanced with better documentation
• Logging and metrics are not applicable as no functional changes were made
• May need to update changelog.md for the partner-chains-node-commands crate to note documentation improvements

[gilligan]

@neotheprogramist let's limit the scope of this PR to just rust docs. I would suggest to drop those markdown files for now. They look very neat but also fall somewhat out of line.

So let's focus on rust-docs for the code.