test(architecture): prove released pkgviz on Eddy

[artiphishle]

Goal

Complete #8 as the real Java end-to-end proof required by PKGViz #262 and Dependency Graph #24.

The proof runs only released registry packages and verifies:

• real Eddy Java detection through the canonical SourceGraph
• package projection plus architecture detection in the same audit
• no enforcement target for detection-only mode
• explicit layered target in a second advisory audit
• generic Rules architecture output alongside the cycle rule
• persisted audit artifacts for inspection

The workflow initially probes the already-published pkgviz@0.8.2; if its immutable tarball predates #262, the failed proof will make that release boundary explicit and the workflow will be moved to the next publishable PKGViz version.

Refs #8
Refs ankhorage/atlas#262
Refs ankhorage/dependency-graph#24
Refs ankhorage/rules-architecture#1