fix(localstore): leveldb-batch based transactions for both index and chunkstore for every localstore op

[istae]

Checklist

• [x] I have read the coding guide.
• [ ] My change requires a documentation update, and I have done it.
• [x] I have added tests to cover my changes.
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Description

An extensive cleanup of the db transaction. Every localstore write operation now utilizes a transaction. Calls to the chunkstore are also part of the transaction.

also tackled: evict just enough chunks of a batch to fall below the reserve capacity

Open API Spec Version Changes (if applicable)

Motivation and Context (Optional)

Related Issue (Optional)

closes #4341 #4538

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