Dependency pruning

[ayushjain17]

Problem

1. make run compiles code twice
2. Redundant dependencies across all crates
3. Single use dependency specified at workspace Cargo.toml
4. superposition_types uses diesel as dependency, which causes dependency issues in 3rd party repos using this crate
5. dependencies in random order
6. cac_client returning data of types superposition_types::result::Result<T> in cases where the return should neither be a Result type or can simply be a Result<T, String>

Solution

1. Remove redundant compile step
2. Remove unused dependencies, mandate #![deny(unused_crate_dependencies)] for all crates
3. Localise single use dependency to the crates instead of workspace Cargo.toml
4. make result type as a feature for superposition_types (make diesel optional)
5. sorted dependencies in alphabetical order
6. Update return type of cac_client functions to direct T or Result<T, String>