Fix spotless:apply failure on modern JDKs

[Divyansh-db]

Summary

• Pin google-java-format to 1.22.0 in the root pom.xml so mvn spotless:apply stops crashing on modern JDKs
  (the code generator runs on JDK 25, where spotless-maven-plugin 2.30.0's bundled GJF 1.15.0 throws
  NoSuchMethodError against the renamed com.sun.tools.javac.util.Log$DeferredDiagnosticHandler.getDiagnostics()
  signature). 1.22.0 is the last GJF release that still supports JRE 11, keeping local dev and the JDK 11 fmt CI job
  working.
• Add scripts/mvn-spotless-apply.sh, a drop-in wrapper that exports MAVEN_OPTS with the
  --add-exports=jdk.compiler/com.sun.tools.javac.*=ALL-UNNAMED flags required by GJF on JDK 16+. It detects the JDK
  major version and only sets the flags when needed, so older JDKs (including the JDK 8 CI matrix rows) are untouched.
  .codegen.json's post_generate now invokes the wrapper instead of mvn spotless:apply directly, mirroring the
  existing bash scripts/cleanup-services.sh pattern.
• One-time reformat of 6 files (16 blank lines inserted, 0 deletions) to satisfy GJF 1.22.0's stricter rules around
  blank lines between documented fields. No semantic changes.

Why a wrapper script and not .mvn/jvm.config?

.mvn/jvm.config applies to every Maven invocation, and this repo's CI matrix runs mvn test / release jobs under
JDK 8, where --add-exports is an unrecognized arg and Maven would fail to start. Scoping the flags to the one
command that actually needs them (spotless:apply) avoids that blast radius.

Impact on CI

• fmt (JDK 11 → spotless:check): GJF 1.22.0 loads fine on JRE 11.
• unit-tests matrix (JDK 8/11/17/20 → mvn test): unaffected, spotless plugin has no <execution> binding so it
  never runs during tests.
• release-build-check / package (JDK 8): unaffected, same reason.
• Compiled bytecode target remains Java 8; GJF only reformats source whitespace.

Test plan

• mvn spotless:check passes on local JDK 11 after the reformat
• mvn spotless:apply on clean HEAD (after pom bump) produces the expected 6-file reformat only; subsequent runs
  are no-ops (idempotent)
• bash scripts/mvn-spotless-apply.sh on JDK 11 correctly skips the MAVEN_OPTS export (JDK < 16) and
  delegates to mvn spotless:apply with BUILD SUCCESS
• CI green across all matrix rows (JDK 8/11/17/20 unit-tests, JDK 11 fmt, JDK 8 release-build-check)

NO_CHANGELOG=true

[github-actions]

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Trigger:
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Inputs:

• PR number: 777
• Commit SHA: b3daa40298ab78b6578dec06114948a12d6de193

Checks will be approved automatically on success.