review: a cancelled turn keeps its trace, and a quiet box still expires (V-629)

Two defects found reviewing the PR.

The insert ran on the turn's own context, so a caller that hung up or timed out
cancelled it. That is exactly the turn worth having. It now runs detached, with
a one-second bound of its own, because a write must not hold the reply.

Retention was enforced on write alone, so a box that goes quiet for a month kept
every row until the next sixty-fourth turn. pruneTracesOnStart closes that, and
RoutingTraceRetention is exported so the daemon reads the same number the store
enforces.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_0117tgnmbgZpHVV3XSNw8Qua

internal/store/migrations.go

@@ -311,7 +311,7 @@ ALTER TABLE reminders ADD COLUMN next_fire_ts INTEGER;`, // #2
 	// sentence is substantially recoverable, so storing vectors instead would be a
 	// privacy claim we cannot support. What makes it safe is the same thing that
 	// makes the fact store safe: it never leaves the box, retention is bounded at
-	// routingTraceRetention, and Wipe drops it with everything else.
+	// store.RoutingTraceRetention, and Wipe drops it with everything else.
 	//
 	// correction is empty until the owner corrects a turn on /chat (V-630). A
 	// corrected pair is promoted out of here into a seed-shaped row and kept, so

internal/store/routingtraces.go

@@ -7,7 +7,7 @@ import (
 	"time"
 )
 
-// routingTraceRetention is how long a raw trace lives (owner's call,
+// RoutingTraceRetention is how long a raw trace lives (owner's call,
 // 06-08-2026). A trace is read within a day or two of the turn that produced it,
 // or never, so two weeks is diagnosis with room for a weekend. It is deliberately
 // an age and not a row count: the useful question is "what did she do this week",
@@ -17,7 +17,7 @@ import (
 // turn, the pair is promoted out of the trace into a seed-shaped row and kept
 // indefinitely, because a label is not a transcript. Keeping the transcript that
 // carried it would defeat the point of the bound.
-const routingTraceRetention = 14 * 24 * time.Hour
+const RoutingTraceRetention = 14 * 24 * time.Hour
 
 // RoutingTrace is one turn's arbitration, persisted. It is internal/decision's
 // Record plus the four things the ring never had to carry: which reach the
@@ -70,7 +70,7 @@ func (s *Store) WriteRoutingTrace(ctx context.Context, tr RoutingTrace) (int64,
 	// Prune rarely. Turns arrive at human rate, so the bound is a ceiling and
 	// paying for a delete on every one of them buys nothing. 64 turns is hours.
 	if id%64 == 0 {
-		if err := s.PruneRoutingTraces(ctx, tr.Ts.Add(-routingTraceRetention)); err != nil {
+		if err := s.PruneRoutingTraces(ctx, tr.Ts.Add(-RoutingTraceRetention)); err != nil {
 			return id, err
 		}
 	}

internal/store/routingtraces_test.go

@@ -62,7 +62,7 @@ func TestPruneRoutingTracesByAge(t *testing.T) {
 			t.Fatal(err)
 		}
 	}
-	if err := s.PruneRoutingTraces(ctx, now.Add(-routingTraceRetention)); err != nil {
+	if err := s.PruneRoutingTraces(ctx, now.Add(-RoutingTraceRetention)); err != nil {
 		t.Fatal(err)
 	}
 	got, err := s.RecentRoutingTraces(ctx, 10)