✨ Return/store/log the VM ExitMessage somewhere

[Thomasvdam]

✨ Feature

When the WasmVM exits with a non-zero exit code that's from Wasmer (or the library I imagine) the result only has details in the ExitInfo.ExitMessage attribute. An example: "Error: Failed to create WASMER instance: Error while importing \"wasi_snapshot_preview1\".\"random_get\": unknown import. Expected Function(FunctionType { params: [I32, I32], results: [I32] })". Right now this data is not written to the result or stored/logged anywhere else. It would be helpful for these messages to be written to the result, stderr, or something else where it's easy to access for the developer.

Motivation

Make errors more transparent and easier to debug.

Implementation

• Decide where this information should be written. Result seems a likely candidate since a VM error means there is no userland result, but stderr might also make sense since it's on the tally side.
• Implement decision.