Remove `isolatedDeclarations` dependency

[chrisbbreuer]

Clear and concise description of the problem

Much of our codebase could already be used in furtherance of this, similar to https://github.com/KermanX/simple_ts

Suggested solution

Benchmark the isolatedDeclaration vs non-isolatedDeclaration approaches

Alternative

No response

Additional context

Initial support for this should be our v2.0 flagship feature.

Validations

• Follow our Code of Conduct
• Read the Contributing Guide.
• Check that there isn't already an issue that request the same feature to avoid creating a duplicate.