Add span origin provenance

[Stephen Belanger (Qard)]

Summary

Adds span origin provenance configuration and OpenTelemetry context propagation to the Java SDK.

Validation

• JAVA_HOME=/opt/homebrew/opt/openjdk@17/libexec/openjdk.jdk/Contents/Home PATH=/opt/homebrew/opt/openjdk@17/bin:/Users/stephenbelanger/.nvm/versions/node/v26.3.1/bin:/opt/homebrew/bin:/opt/homebrew/sbin:/usr/local/bin:/System/Cryptexes/App/usr/bin:/usr/bin:/bin:/usr/sbin:/sbin:/var/run/com.apple.security.cryptexd/codex.system/bootstrap/usr/local/bin:/var/run/com.apple.security.cryptexd/codex.system/bootstrap/usr/bin:/var/run/com.apple.security.cryptexd/codex.system/bootstrap/usr/appleinternal/bin:/pkg/env/global/bin:/Library/Apple/usr/bin:/opt/homebrew/Caskroom/codex/0.144.1/codex-path:/Users/stephenbelanger/.codex/tmp/arg0/codex-arg0hCuz7e:/Users/stephenbelanger/.rbenv/shims:/Users/stephenbelanger/.g/bin:/Users/stephenbelanger/.g/go/bin:/Users/stephenbelanger/go/bin:/Users/stephenbelanger/.nvm/versions/node/v26.3.1/bin:/Users/stephenbelanger/.local/bin:/Users/stephenbelanger/.swiftly/bin:/Users/stephenbelanger/.cargo/bin:/Applications/Ghostty.app/Contents/MacOS:/Users/stephenbelanger/.lmstudio/bin ./gradlew :braintrust-sdk:test
• aggregate git diff --check