Add Assembly, Dart, Swift, R, and Groovy

[kserrec]

Summary

• add self-checking Lambda Core implementations for Assembly, Dart, Swift, R, and Groovy
• add standalone READMEs, test wrappers, and observed output baselines
• run Groovy through either its native runtime or Gradle's embedded Groovy runtime
• install only the missing R and Dart toolchains in CI

Verification

• exact baseline checks passed for all five implementations
• Groovy passed both direct Groovy 5 and Gradle 9 execution paths
• Dart analysis reported no issues
• repository harness: 12 passed, 0 failed, 13 locally unavailable toolchains skipped, 1 pre-existing Java baseline pending

The Dart setup action is pinned to signed v1.7.2 because upstream v1.8.1 currently has a published-bundle regression (dart-lang/setup-dart#198).

[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-08-31T00:40:33.647978Z	5a972b1	PR opened

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