RoslynScriptedAlarmEvaluator mirrors F8b's pattern for alarm predicates:
caches a compiled ScriptEvaluator<AlarmPredicateContext, bool> per unique
predicate, runs against the dependency dictionary with a 2s timeout, and
turns every failure (compile error, sandbox violation, runtime throw,
ctx.SetVirtualTag attempt — predicates must be pure) into a
ScriptedAlarmEvalResult.Failure. ScriptedAlarmActor preserves prior state
on Failure so a broken predicate can't flip Active/Inactive spuriously.
Program.cs binds both evaluators on driver-role hosts — this fully
satisfies #107 ("bind production VirtualTagEngine + ScriptedAlarmEngine
adapters"). The two Roslyn adapters together replace the F8 + F9 Null
defaults, so VirtualTagActor + ScriptedAlarmActor now run real user
scripts in production.
7 new adapter tests cover: predicate true → Active, predicate false →
Inactive, cache reuse, compile-error denial, write-attempt denial,
empty-predicate denial, post-dispose denial. Host.IntegrationTests now
17/17 green.
Closes#80 + #107. All major v2 follow-ups are now complete; only
cleanup + observability polish remains.
