Add Qdrant vector database REST wrapper

[jynbil1]

Summary

• add a Qdrant REST API wrapper under the JavaScript vector-db module
• export Qdrant and QdrantDistanceMetric from vector-db
• add focused tests for client creation, collection creation, upsert, search, and delete

Validation

• npm run build
• npx jest src/vector-db/src/tests/qdrant/qdrant.test.ts --runInBand

Closes #273

[github-actions]

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[chatgpt-codex-connector]

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[chatgpt-codex-connector]

Allow named-vector query shape in search args

QdrantVector is reused for searchPoints, but its object branch is Record<string, number[]>, which rejects Qdrant's valid named-vector search payload shape ({ vector: number[], name: string }). In a strict TypeScript project, this makes multi-vector searches fail at compile time unless callers cast to any, effectively breaking a supported Qdrant search mode introduced by this wrapper.

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