[#824] General cleanup

Description

While working on #824 (closed), I happened to come across a few unrelated things that needed to be cleaned up and a bug:

• We should enable the InstanceSigs extension globally
• In the Pure module, we were using Text where we should have been using the Alias data type.
• We had no tests for cleveland's resolveAddress
• Bug: In Pure, when a contract fails, we were enriching the ExecutorError with the contract's alias - however, the exceptionHandler was discarding this data, so the contract's alias never showed up in error messages as intended.

This MR fixes all of the above.

Related issue(s)

Resolves part of #824 (closed)

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