[ENH] Get vectors orchestrator

[HammadB]

This PR adds the Get Vectors() RPC for query nodes.

1. Adds the GetVectors instrumented rpc call and associated types
2. Adds a GetVectorsOrchestrator for managing these queries
3. Adds the GetVectorsOperator for reading from the log and record segment to respond to get_vectors
4. Moves common orchestrator functions into a /common and refactors hnsw orchestrator to use this instead (DRY)
5. Adds the ChromaError Trait for ChannelError in Sender - needed to use that as Box elsewhere.

I explicitly make the choice to not have to materialize in this operator since it doesn't need to for any reason.

Tasks

• [x] Stub out
• [x] Types
• [x] Implement return
• [x] Server input parse
• [x] Server output parse
• [x] Init segments
• [x] Pull log + filter
• [x] Operator for reading
• [x] Add test (Will handle in separate PR)
• [x] Validate that the get() semantics for missing ids is correct (I have validated that the semantics are the same - we just ignore invalid entries in the output)

[github-actions[bot]]

Reviewer Checklist

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Testing, Bugs, Errors, Logs, Documentation

• [ ] Can you think of any use case in which the code does not behave as intended? Have they been tested?
• [ ] Can you think of any inputs or external events that could break the code? Is user input validated and safe? Have they been tested?
• [ ] If appropriate, are there adequate property based tests?
• [ ] If appropriate, are there adequate unit tests?
• [ ] Should any logging, debugging, tracing information be added or removed?
• [ ] Are error messages user-friendly?
• [ ] Have all documentation changes needed been made?
• [ ] Have all non-obvious changes been commented?

  System Compatibility

• [ ] Are there any potential impacts on other parts of the system or backward compatibility?
• [ ] Does this change intersect with any items on our roadmap, and if so, is there a plan for fitting them together?

  Quality

• [ ] Is this code of a unexpectedly high quality (Readability, Modularity, Intuitiveness)