Add Supercov to Code Coverage

[Nedomas]

Suggestion type

• Project
• Resource

Adds Supercov under Code Coverage in README_SOURCE.md.

Supercov measures line, branch and MC/DC coverage of Java and Kotlin test runs (supercov -- mvn test, supercov -- ./gradlew test) without changing the build, and scores source files for code quality with TypeSafe Jev so a coding agent knows what to fix first. Java guide: https://supercov.com/docs/java. MIT licensed.

Checklist

• I searched the list and existing issues for duplicates.
• I changed README_SOURCE.md, not the generated README.md.
• This pull request contains one suggestion.
• The suggestion is relevant to Java or the JVM and fits its chosen category.
• I used the canonical project or resource link.
• The suggestion is current and maintained.
• The concise, neutral description explains its distinguishing value and ends with punctuation.
• Licensing is clear and any restrictive terms are disclosed where applicable.

Disclosure: I maintain Supercov (Supercorp). It is free, open source and MIT licensed; the quality half calls TypeSafe Jev under the user's own key, the coverage half needs no account. Prepared with AI assistance and reviewed by me.

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Summary by cubic

Adds Supercov to the Code Coverage section of README_SOURCE.md; it measures line, branch, and MC/DC coverage of Java and Kotlin test runs without changing the build and scores source files for code quality. The generated README.md is not updated.

^{Written for commit bb0682d. Summary will update on new commits.}

[cubic-dev-ai]

All reported issues were addressed across 1 file

<sub>Reply with feedback, questions, or to request a fix.

Re-trigger cubic</sub>

[Nedomas]

Updated the Supercov entry to describe its Java/Kotlin coverage and code quality scoring in neutral terms. The validation and AI review checks now pass, and the review issue is resolved. @akullpp, could you review the PR when you have a chance?