Consolidate workspace metadata

[ok300]

Since the crates are organized in a workspace, we can define most metadata fields in the workspace Cargo.toml and simply reference them in the member crates Cargo.tomls.

This makes maintenance easier. For example, version needs to be updated only in one place when releasing a new version. At the same time, it also gives us the flexibility to set a custom value for a member crate and overwrite the workspace value, if needed.

Note: In dependencies that were specified by path, like

cdk = { path = "../cdk", version = "0.4.0", default-features = false, features = ["mint"] }

the version was removed, since it's ignored by Cargo anyway. Instead, Cargo uses the code under that path, regardless of specified version.

[ok300]

Too bad, looks like the workspace-inheritance feature is only available starting with MSRV 1.64.0, which is higher than the current 1.63.0.