feat(canon): M1.3 enroll all 21 used-recipes as data-warm canonicals (§2.B)

WARM_CANONICAL=True added to every recipe in cc-ci-plan/used-recipes.md (20 weekly +
uptime-kuma external). enrolled_recipes() now returns all 21. Test fixtures
(custom-html-*-bad, concurrency, regression) intentionally left unenrolled.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

tests/cryptpad/recipe_meta.py

@@ -13,3 +13,8 @@ def EXTRA_ENV(ctx):
     (covered by the wildcard cert, so no cert work)."""
     label, _, rest = ctx.domain.partition(".")
     return {"SANDBOX_DOMAIN": f"{label}-sb.{rest}"}
+
+
+# canon §2.B: enroll as a DATA-WARM canonical (all recipes enrolled — operator 2026-06-17).
+# The weekly sweep promotes this recipe's canonical to its latest green RELEASE TAG.
+WARM_CANONICAL = True