fix(parser): allow VPC envelopes to handle non-JSON strings

[dreamorosi]

Summary

Changes

Please provide a summary of what's being changed

This PR updates the implementation of both the VPC Lattice v1 & v2 envelopes so that they don't try transform the body of the request as JSON without the customer explicitly passing a schema that does so.

This allows customers to handle plain text or base64-encoded as well.

In this PR I also removed the @anatine/zod-mock dependency, moved the packages/parser/tests/schemas/util.js file to its own folder at packages/parser/tests/helpers/util.js, and removed the Envelope implementation since this was the last set of built-in envelopes using it. These three changes account for 90% of the diff.

Also with this PR we should be done with the major refactoring of the Parser envelopes. There are still a few things we should address like improving the docstrings of some envelopes/schemas, improving the docs of the utility, and creating sub-path exports for each set of envelopes like we did for the built-in schemas - but we'll do this in the next releases.

Please add the issue number below, if no issue is present the PR might get blocked and not be reviewed

Issue number: fixes #3533

---

By submitting this pull request, I confirm that you can use, modify, copy, and redistribute this contribution, under the terms of your choice.

Disclaimer: We value your time and bandwidth. As such, any pull requests created on non-triaged issues might not be successful.

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[am29d]

Well done, thanks a lot for the moving the bug bash forward so quickly!