feat: Add Protobuf support for Explain node

[danielhumanmod]

Which issue does this PR close?

• Closes #.

Rationale for this change

EXPLAIN FORMAT TREE is supported in logical plans, but protobuf serialization did not preserve the explain format.

In Datafusion Ballista, we need the format field to generate corresponding distributed plan.
apache/datafusion-ballista#1627 (comment)

What changes are included in this PR?

• Add ExplainFormat to protobuf common definitions.
• Add the format field to protobuf ExplainNode.
• Regenerate protobuf code.

Are these changes tested?

Yes, we add a roundtrip test for EXPLAIN FORMAT TREE.

Are there any user-facing changes?

No

[github-actions]

Thank you for opening this pull request!

Reviewer note: cargo-semver-checks reported the current version number is not SemVer-compatible with the changes in this pull request (compared against the base branch).

Details

     Cloning apache/main
    Building datafusion-proto v53.1.0 (current)
       Built [  59.399s] (current)
     Parsing datafusion-proto v53.1.0 (current)
      Parsed [   0.136s] (current)
    Building datafusion-proto v53.1.0 (baseline)
       Built [  56.929s] (baseline)
     Parsing datafusion-proto v53.1.0 (baseline)
      Parsed [   0.140s] (baseline)
    Checking datafusion-proto v53.1.0 -> v53.1.0 (no change; assume patch)
     Checked [   1.646s] 222 checks: 221 pass, 1 fail, 0 warn, 30 skip

--- failure constructible_struct_adds_field: externally-constructible struct adds field ---

Description:
A pub struct constructible with a struct literal has a new pub field. Existing struct literals must be updated to include the new field.
        ref: https://doc.rust-lang.org/reference/expressions/struct-expr.html
       impl: https://github.com/obi1kenobi/cargo-semver-checks/tree/v0.47.0/src/lints/constructible_struct_adds_field.ron

Failed in:
  field ExplainNode.format in /home/runner/work/datafusion/datafusion/datafusion/proto/src/generated/prost.rs:355
  field ExplainNode.format in /home/runner/work/datafusion/datafusion/datafusion/proto/src/generated/prost.rs:355

     Summary semver requires new major version: 1 major and 0 minor checks failed
    Finished [ 120.352s] datafusion-proto
    Building datafusion-proto-common v53.1.0 (current)
       Built [  22.615s] (current)
     Parsing datafusion-proto-common v53.1.0 (current)
      Parsed [   0.045s] (current)
    Building datafusion-proto-common v53.1.0 (baseline)
       Built [  22.414s] (baseline)
     Parsing datafusion-proto-common v53.1.0 (baseline)
      Parsed [   0.047s] (baseline)
    Checking datafusion-proto-common v53.1.0 -> v53.1.0 (no change; assume patch)
     Checked [   0.962s] 222 checks: 222 pass, 30 skip
     Summary no semver update required
    Finished [  47.757s] datafusion-proto-common

[Jefffrey]

We probably should format the error like so:

datafusion/datafusion/proto/src/logical_plan/mod.rs

Lines 835 to 841 in 7d107f0

	let join_type =
	protobuf::JoinType::try_from(join.join_type).map_err(|_| {
	proto_error(format!(
	"Received a JoinNode message with unknown JoinType {}",
	join.join_type
	))
	})?;

• Using proto error variant, and also including the invalid format for visibility

[danielhumanmod]

good catch, fixed in the latest commit, thanks!

[milenkovicm]

thanks @danielhumanmod and @Jefffrey for review