Assemble external workspace dependencies into Cargo dependencies

[flyingsilverfin]

What is the goal of this PR?

Assembling a Rust crate failed to convert external bazel workspace dependencies into Crate depedencies using the external dependency's version, as specified by workspace refs. We now use workspace references to correctly convert external rust library dependencies into crate dependencies, with version specifiers.

In addition, we now package README and LICENSE files into the generate crate.

What are the changes implemented in this PR?

• Experimental: delete metadata generation from Crate assembly, it may not be required
• Add workspace refs to crate assembly, which converts external bazel workspace dependencies into correctly versioned crate manifest dependencies
• add license and readme's into generated crate tarballs

[vaticle-bot]

PR Review Checklist

Do not edit the content of this comment. The PR reviewer should simply update this comment by ticking each review item below, as they get completed.

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Trivial Change

• [x] This change is trivial and does not require a code or architecture review.

Code

• [ ] Packages, classes, and methods have a single domain of responsibility.
• [ ] Packages, classes, and methods are grouped into cohesive and consistent domain model.
• [ ] The code is canonical and the minimum required to achieve the goal.
• [ ] Modules, libraries, and APIs are easy to use, robust (foolproof and not errorprone), and tested.
• [ ] Logic and naming has clear narrative that communicates the accurate intent and responsibility of each module (e.g. method, class, etc.).
• [ ] The code is algorithmically efficient and scalable for the whole application.

Architecture

• [ ] Any required refactoring is completed, and the architecture does not introduce technical debt incidentally.
• [ ] Any required build and release automations are updated and/or implemented.
• [ ] Any new components follows a consistent style with respect to the pre-existing codebase.
• [ ] The architecture intuitively reflects the application domain, and is easy to understand.
• [ ] The architecture has a well-defined hierarchy of encapsulated components.
• [ ] The architecture is extensible and scalable.