## Description 

This is a follow up change after PR #17508 , for
[SIP-19](https://github.com/sui-foundation/sips/blob/main/sips/sip-19.md).

The changeset focuses on sui-core, particularly authority server, to add
a new API `SoftBundleCertifiedTransactionsV3` that allows submission of
a Soft Bundle through gRPC.

The API accepts a list of `CertifiedTransaction` for input, then returns
either nothing (should `wait_for_effects` be `false`) or a list of
`HandleCertificateResponseV3` containing the execution result.

The API is named `_v3` because it reuses `HandleCertificateResponseV3`. 

Besides introducing a new feature flag and a protocol config field, a
local node config field `enable_soft_bundle` is also added, to allow a
validator node to turn off soft bundle support without having to upgrade
the entire network. This can be useful should the feature causes
undesired effect.

## Test plan 

The feature is not exactly user-facing and do not break anything.

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## Release notes

- [x] Protocol: New feature flag and protocol config fields will be
introduced.
- [x] Nodes (Validators and Full nodes): A new API
`SoftBundleCertifiedTransactionsV3` will be added.
- [ ] Indexer: 
- [ ] JSON-RPC: 
- [ ] GraphQL: 
- [ ] CLI: 
- [ ] Rust SDK:

---------

Co-authored-by: Mark Logan <mark@mystenlabs.com>