feat: jsonb || operator

[taytzehao]

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What's changed and what's your intention?

fix #12180 This PR adds the jsonb concatenation operator. The concatenation takes into consideration 4 situations ie

1. both inputs are objects, the return type would be jsonb object
2. both/either inputs are array, the return type would be a jsonb array
3. for other situations, both inputs would be placed into an array4.
   The limitation of this PR is that it only concatenates when both data type are jsonb. If either data type is not jsonb, a binding error would still be present.

Checklist

• I have written necessary rustdoc comments
• I have added necessary unit tests and integration tests
• I have added fuzzing tests or opened an issue to track them. (Laptop space is running low to run it locally, any tips to run it with minimal space?).
• All checks passed in ./risedev check (or alias, ./risedev c)

Documentation

• My PR needs documentation updates. (Please use the Release note section below to summarize the impact on users)

Release note

If this PR includes changes that directly affect users or other significant modifications relevant to the community, kindly draft a release note to provide a concise summary of these changes. Please prioritize highlighting the impact these changes will have on users.

RELEASE NOTE:
Added operator that allow jsonb data types to be concatenated. Documentation PR is here.

[xiangjinwu]

Thank you for the contribution!

[xiangjinwu]

It is an anti-pattern to

• take serde_json::Value out of JsonbRef
• process serde_json::Value
• put processed serde_json::Value back into a JsonbVal

because we may switch away from serde_json #11805. This pattern is a leak of implementation detail.

However, avoiding this means moving the concat implementation to common crate, which could hurt build time #12485

cc @wangrunji0408 @xxchan It's up to you how we proceed with the code organization.

[xxchan]

Since the complexity is not very high, I feel comfortable to proceed in whatever way. 🤣