Importing any classes from @minecraft/server causes the assertion error: "Failed to resolve base class"

Summary:
Importing any classes from `@minecraft/server` version 1.2.0 causes an assertion error when logging into the world.

Verification Build:
1.20.0

Regression Builds:
1.19.81

Impact:
This causes an assertion error. All of the content continues to work as expected, but could cause working content to be flagged by review.

Repro Steps:
1. Create a behavior pack that includes scripts.

2. Import any class from @minecraft/server, for example:
import { world } from "@minecraft/server";
world;
3. Attach the behavior pack to a world and you will receive an assertion error on login.
An mcworld has been attached that demonstrates the error.
Observed Results:
Including built in @minecraft/server classes causes an assertion error.

Expected Results:
Including built in @minecraft/server classes causes no errors.