Conformance test suite for AEX v2 (ADR-0048).

Each test is an async function that returns Result<(), ConformanceFailure>. The library exposes them as a flat list so the binary can iterate, capture results, and print a summary; downstream code (CI integrations, dashboards) can also import the list and slice it by category.

Scope at v2.0 GA

Offline checks of the local AEX stack: wire-v2 round-trip, JWS algorithm whitelist enforcement, SSRF resistance of safe_http, clock-skew handling, capability registry stability, DID URI parser strictness, cross-version isolation between v1 and v2. Network-aware checks against a remote control plane URL stage as v2.1.