Add a plugin point for framework sources (#6735)

[clockard]

What does this PR do?

Forward port of https://github.com/codice/ddf/pull/6735

Who is reviewing it?

@derekwilhelm @glenhein @jlcsmith

How should this be tested?

Good CI Build

Any background context you want to provide?

What are the relevant tickets?

Fixes: #____

Screenshots

Checklist:

• [ ] Documentation Updated
• [ ] Update / Add Threat Dragon models
• [ ] Update / Add Unit Tests
• [ ] Update / Add Integration Tests

Notes on Review Process

Please see Notes on Review Process for further guidance on requirements for merging and abbreviated reviews.

Review Comment Legend:

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• ❗ (Exclamation Mark) This comment is critical and requires clarification or action before approval.

[clockard]

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