refactor: switch CLI argument parsing to clap

[jsturtevant]

Replaces manual command-line argument parsing with clap derive macros.

Changes

• Add clap dependency with derive feature
• Define Cli struct with clap attributes for argument parsing
• Convert --setup-registry and --clear-registry flags to subcommands (setup-registry, clear-registry)
• Maintain --verbose as a flag
• Script path is now a positional argument

Usage

# Run scripts
cargo run -- guest-examples/hello.js
cargo run -- --verbose guest-examples/hello.py

# Subcommands
cargo run -- setup-registry
cargo run -- clear-registry

# Help
cargo run -- --help

[jsturtevant]

should retrigger ci once #26 is in

[Copilot]

Pull request overview

This PR refactors the CLI argument parsing from manual implementation to using the clap derive macros, improving maintainability and user experience.

Changes:

• Replaces manual argument parsing with clap's derive API
• Converts --setup-registry and --clear-registry flags to subcommands
• Changes script path from a searched argument to a proper positional parameter

Reviewed changes

Copilot reviewed 1 out of 3 changed files in this pull request and generated no comments.

File	Description
Cargo.toml	Adds clap dependency with derive feature
Cargo.lock	Adds clap and its dependencies to the lock file
src/bin/hyperlight-nanvix.rs	Implements clap-based CLI with Cli struct, Commands enum, and updated main function

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[Copilot]

Pull request overview

Copilot reviewed 3 out of 5 changed files in this pull request and generated no new comments.

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