docs(tooling): add sub-processor discriminated union to ADR-022 and traces

Amends ADR-022 §9 with the `is-sub-processor` / `processes-pii` discriminated
union spec, including the five conditional fields required when a library is a
true GDPR sub-processor. Updates the evaluate-library skill to prompt for these
fields during every trace authoring pass and adds the updated frontmatter
template. Backfills all nine existing library-decision traces with the new
fields; payload gets `processes-pii: true` (self-hosted CMS that stores user
data); all pure in-process libraries get `false / false`.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

docs/library-decisions/2026-05-14-react-dom.md

@@ -6,6 +6,9 @@ decision: approved
 date: 2026-05-14
 deciders: [Danijel Martinek]
 adr: null
+lastRevalidated: null
+is-sub-processor: false
+processes-pii: false
 filter-results:
   license: MIT
   types: native