[WIP] Simplify Framework registration

[gdavison]

Rollback Plan

If a change needs to be reverted, we will publish an updated version of the library.

Changes to Security Controls

Are there any changes to security controls (access controls, encryption, logging) in this pull request? If so, explain.

Description

Uses sync.Once instead of mutex and boolean to ensure schema validation is called once.

Simplifies Framework Data Source registration:

• Defers creating inner wrapped resource until wrapper is called
• Makes boostrapContext a method on wrappedDataSource instead of function pointer
• Encapsulates configuration of interceptors

[github-actions]

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[ewbankkit]

As this returns an error should we prefer sync.OnceValue?

[gdavison]

Yeah, I thought about that. I see sync.OnceValue as more "return a useful value", but since the error manages the control flow, that counts as a "useful value"

[ewbankkit]

Maybe just context (or Context) is now a better name for this method?