[hdcodedev]

Summary

• Refresh Gradle task outputs after source changes on main, using a separate cache keyed by OS, architecture, and commit. Pull requests restore the latest available outputs for their platform.
• Exclude task outputs from the dependency cache and keep task-output saves in the warm workflow.
• Document the cache flow and record the decision with verification pending in the decision log.

Fixes #746.

Follow-up verification: #801. After merge, check a successful warm run on main and a subsequent code PR. Check Kotlin compile/link cache hits, archive sizes, and job timings; record the result in the decision log.

Local Validation

• Passed YAML parsing:

  ruby -e 'require "yaml"; ARGV.each { |p| YAML.parse_file(p); puts "Parsed #{p}" }' .github/actions/setup-jdk/action.yml .github/workflows/warm-gradle-cache.yml

• Passed git diff --check and git diff --cached --check.
• No local Gradle commands run. Build and test validation will run in PR CI; task-output reuse requires a successful warm run on main after merge.