Test Claritas dependency-graph package projection end-to-end #182

Add an E2E lane that installs Claritas graph-model/layout/renderer-adapter packages through zed-pkg, loads a canonical dependency graph, and verifies the same graph can be consumed by Rust/WASM, TypeScript/HTML, Dart/Flutter, Dioxus/Leptos/Mash Rust, WebView, Qt/QML, and Web Components adapters. Acceptance: frozen lockfile, deterministic node/edge identity, no Claritas server required for final render, and exact parity with claritas-viz-test/rendering-golden.