Fix workflow inference for non-JS source files

[MageByte-Zero]

Summary

• Expand workflow auto-detection so common non-JavaScript source files are recognized as code files.
• Prevent multi-task Java, Go, Python, Rust, and similar code changes from being misclassified as config/doc-only tweak work.
• Prepare the 0.8.12 patch release.

Root Cause

infer-workflow.mjs only recognized JavaScript/TypeScript extensions as code files, and its file-matching regex used the same narrow extension set. Paths like src/Main.java, cmd/server/main.go, app/worker.py, and src/parser.rs were ignored by file collection, so multi-task code changes could fall through into the tweak path.

Verification

• node --test tests/lib/infer-workflow.test.mjs
• CLI repro for a 3-task Go change now returns full
• npm run build
• npm test
• node scripts/spec-superflow.mjs doctor
• node scripts/check-version-consistency.mjs

Fixes #19