This change moves the fault injection logic directly into the
opendc-compute-simulator module, so that it can operate at a higher
abstraction. In the future, we might again split the module if we can
re-use some of its logic.

This change adds support for specifying the distribution of the
failures, group size and duration for the fault injector.

This change adds support for the Gradle version catalog feature in our
build configuration. This allows us to have a single file,
gradle/libs.versions.toml, which contains all the dependency versions
used in this project.

This change updates the build scripts to use type-safe project accessors
when specifying build dependencies between modules.

This change updates the project structure to become flattened.
Previously, the simulator, frontend and API each lived into their own
directory.

With this change, all modules of the project live in the top-level
directory of the repository. This should improve discoverability of
modules of the project.