Encapsulate HolonCollection behind HolonCollection Api

[evomimic]

UNDER CONSTRUCTION

1. Summary (Required)

This enhancement extends the use of HolonCollectionApi introduced in Issue #201 to fully encapsulate the exposure of HolonCollection behind HolonCollectionApi trait objects. It also resolves some minor carryover anomalies from PR #210

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2. Problem Statement (Required)

Some API's still expose concrete structs directly. This limits their utility to only HolonCollections. Changing those API's to return HolonCollectionApi's will broaden their utility while better encapsulating private behaviors.

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3. Dependencies (Required)

Does this depend on other issues or features?
Highlight any blockers or prerequisites that must be addressed before this enhancement can proceed.

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4. Proposed Solution (Required)

Affected Interfaces:

• HolonReadable
• HolonServiceApi

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5. Scope and Impact (Required)

What does this impact?
Outline what parts of the system, user workflows, or broader ecosystem are affected.

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6. Testing Considerations (Required)

How will this enhancement be tested?

• Can it be validated with existing test cases?
• Do new test cases need to be created?
• Are there specific areas in the test ecosystem impacted by this enhancement?

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7. Definition of Done (Required)

When is this enhancement complete?
Provide clear criteria to know when the enhancement has been fully implemented and validated.

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Optional Details (Expand if needed)

8. Alternatives Considered

What other solutions did you think about?
Briefly describe alternatives and why this approach is preferred.

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9. Risks or Concerns

What could go wrong?
Highlight potential challenges, like performance or compatibility issues.

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10. Additional Context

Any supporting material?
Include links, screenshots, logs, or diagrams.

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