docs: point the all-unit-tests command at ./gradlew build

[jbachorik]

What does this change do?

Corrects the "Distribution and all unit tests" command in CLAUDE.md. :btrace-dist:build schedules only 2 of the 24 module test tasks, so following the guide skipped most of the unit suite. ./gradlew build schedules all 24 and still builds the distribution. Found while gating #967.

Related issue

N/A

Scope and compatibility

• I identified the affected module(s) and kept unrelated changes out of this PR.
• This preserves the supported Java/runtime compatibility tiers, or the change is documented below.
• This does not change the masked-JAR layout, class-loader boundary, or wire protocol.
• If it does, I updated the relevant architecture documentation and verification plan.

Compatibility or migration notes: None. Documentation only. AGENTS.md ("Build :btrace-dist:build before integration tests") is accurate and unchanged.

Testing

• Unit tests
• Integration tests (if applicable)
• spotlessCheck
• Documentation/link or sample verification (if applicable)

Commands and results:

./gradlew :btrace-dist:build --dry-run | grep -c ':test SKIPPED$'   -> 2
./gradlew build --dry-run              | grep -c ':test SKIPPED$'   -> 24 (plus :btrace-dist:build)
./gradlew test --dry-run               | grep -c ':test SKIPPED$'   -> 24

Documentation and release impact

• User-facing documentation is updated, or no documentation change is needed.
• Release notes/changelog are updated, or no release-note entry is needed.
• Samples, distribution contents, or published coordinates are updated if affected.
• This change is safe to merge independently of a release, or the dependency is explained below.

Final checklist

• I reviewed the complete diff and removed unrelated changes.
• New or changed behavior has appropriate tests, or the reason for not adding them is explained above.
• User-facing behavior, APIs, samples, and documentation are consistent with this change.
• I did not include generated build output, local configuration, credentials, or other accidental files.

🤖 Generated with Claude Code

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