identity: "apps with access" — per-subject active-grant listing (+7 tests)

identity_tokens:grants_for(Subject) lists a subject's active grants as
[{Client, Scope}] (revoked excluded), exposed through the facade as
identity:grants(Subject). Completes the per-subject account-security trio:
sessions (where logged in), grants (which apps have access), history (what
happened). New tests/account.sx. Conformance internal timeout raised to
1200s (22 suites, ~10min — run in background). 229/229.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

lib/identity/scoreboard.md

@@ -1,6 +1,6 @@
 # identity-on-sx Scoreboard
 
-**Total: 222 / 222 tests passing**
+**Total: 229 / 229 tests passing**
 
 |  | Suite | Pass | Total |
 |---|---|---|---|
@@ -25,6 +25,7 @@
 | ✅ | introspect | 9 | 9 |
 | ✅ | par | 7 | 7 |
 | ✅ | dynreg | 5 | 5 |
+| ✅ | account | 7 | 7 |
 
 
 Generated by `lib/identity/conformance.sh`.