Set up Cargo workspace and standardize dependencies

[dymk]

What changes does this PR introduce?

This PR sets up a Cargo workspace at the repository root and standardizes dependencies across all service crates. It unifies dependency management and makes it easier to maintain consistent versions across crates within the project.

Key changes:

1. Added a root Cargo.toml with workspace configuration
2. Moved common dependency specifications to workspace-level
3. Updated all service crates to use workspace dependencies
4. Added cargo test to GitHub Actions
5. Check no_std targets compile
6. Check rt633 example compiles - the other examples are broken, and can be fixed in a future PR.
7. Cleaned up individual Cargo.toml files for consistent formatting
8. Exclude example directories from the workspace as they are effectively separate projects
9. Commit Cargo.lock to prevent future breakages due to upstream crates

Why?

• Simplifies dependency management across all crates
• Ensures consistent dependency versions
• Makes it easier to update dependencies in one place
• Improves build times through shared target directories
• Ensure tests and builds do not break if changes are made cross-package via CI/CD

[asasine]

Some changes would be good but not blocking on them.