Ability to verify my cargo workspace before packaging but without building.

Problem

Currently packaging verification process run by cargo package and cargo publish runs 2 tasks:

1. Metadata verification.
2. Build a package

First task is just cargo build, the second may emit warnings about some metadata is missing

Good practice on CI is to run sequentially or in parallel

1. Run fast metadata verification, as this process will take short time and it's important. No build required.
2. Build project and run all checks to verify if even some wrong commit was merged, release would be clean

The metadata verification is done by cargo package and if critical field is missing, a warning is emitted. There's no control on which metadata is critical, which is not and there's no way to enforce it.

Additionally, building a package in most cases is a duplication of responsibility of a user to run at least cargo build first.

I understand historical reasons of this solution in cargo package, and I'd like to have an ability to alter this behaviour on demand/company policies, but not remove this step completely

Previous discussion was here: #15398

Proposed Solution

For making build optional I'd like to have configuration variable to be set to control behaviour of cargo verification process.

Notes

No response

Start by reading the cargo package and cargo publish verification flow described in the issue, then review the prior discussion in #15398. Define how a configuration setting would make package building optional while retaining metadata verification. Done means the behavior can be selected on demand without removing the existing verification step.