fix(sandbox): actually delegate getLifecycleDueAtMs to the extracted helpers

In the previous SRP refactor I created computeInactivityDueAtMs.ts and
computeExpiryDueAtMs.ts but the Write to update getLifecycleDueAtMs.ts
errored on "File has not been read yet" and I missed it in the batch
output. The two helper files were left as orphans while the original
file kept its inline copies — visible by the SANDBOX_*_MS imports +
both functions still inlined.
Now properly imports computeInactivityDueAtMs / computeExpiryDueAtMs
and the parent file just composes them. No behavior change.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: sweetmantech

lib/sandbox/getLifecycleDueAtMs.ts

@@ -1,20 +1,11 @@
-import{
-SANDBOX_EXPIRES_BUFFER_MS,
-SANDBOX_INACTIVITY_TIMEOUT_MS,
-}from"@/lib/sandbox/sandboxLifecycleConfig";
-import{isoToEpochMs}from"@/lib/sandbox/isoToEpochMs";
+import{computeExpiryDueAtMs}from"@/lib/sandbox/computeExpiryDueAtMs";
+import{computeInactivityDueAtMs}from"@/lib/sandbox/computeInactivityDueAtMs";
 importtype{Tables}from"@/types/database.types";
 
 /**
  * Computes when the lifecycle workflow should next wake up for a
- * session. Returns the earlier of:
- * - inactivity due — `last_activity_at` (or `updated_at`) +
- * SANDBOX_INACTIVITY_TIMEOUT_MS, overridden by `hibernate_after`
- * if set
- * - expiry due — `sandbox_expires_at` minus
- * SANDBOX_EXPIRES_BUFFER_MS, so we pause before Vercel hard-stops
- *
- * Output is epoch milliseconds. Used by both the workflow (for
+ * session. Returns the earlier of the inactivity-due time and the
+ * expiry-due time. Used by both the workflow (for
  * `sleep(new Date(wakeAtMs))`) and the stale-run detector in the
  * kick logic.
  *
@@ -32,19 +23,3 @@ export function getLifecycleDueAtMs(
 if(expiryDue===null)returninactivityDue;
 returnMath.min(inactivityDue,expiryDue);
 }
-
-functioncomputeInactivityDueAtMs(
-row: Pick<Tables<"sessions">,"hibernate_after"|"last_activity_at"|"updated_at">,
-): number{
-consthibernateAfter=isoToEpochMs(row.hibernate_after);
-if(hibernateAfter!==null)returnhibernateAfter;
-constlastActivity=isoToEpochMs(row.last_activity_at);
-constfallback=lastActivity??isoToEpochMs(row.updated_at)??Date.now();
-returnfallback+SANDBOX_INACTIVITY_TIMEOUT_MS;
-}
-
-functioncomputeExpiryDueAtMs(row: Pick<Tables<"sessions">,"sandbox_expires_at">): number|null{
-constexpiresAt=isoToEpochMs(row.sandbox_expires_at);
-if(expiresAt===null)returnnull;
-returnexpiresAt-SANDBOX_EXPIRES_BUFFER_MS;
-}