Feature: separation of storage and compute

[HuSen8891]

We separate the storage and computer, meta data is stored in catalog service, and user data is stored in data store. QD is responsible for catalog modification、query plan and dispatch; QE is responsible for all operations related with user data, executing queries.

core changes:

1. add macro serverless, configure with --enable-serverless
2. add hooks to get control in transaction/dispatch management.
3. add transaction processing framework.
4. add session state dispatch framework.

Why are the changes needed?

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Does this PR introduce any user-facing change?

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How was this patch tested?

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✅ HuSen8891
❌ husen

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