fix(web): preserve batch contract on scheduler failures

tools/web/run-wbv2-scheduler.mjs

@@ -219,6 +219,15 @@ function sourceMappingReadiness(pointer) {
   const card = read(cardPath);
   const implementation = card.match(/- Implementation entrypoint: `([^`]+)`/u)?.[1];
   if (!implementation) return { ok: false, reason: "implementation_entrypoint_missing", taskClass };
+  if (/targetImplementationClass:\s*LOCAL_EXACT/u.test(card)) {
+    const batchId = card.match(/^- batchId:\s*`?([^`\n]+)`?/mu)?.[1];
+    const selected = card.match(/^- selectedRecordIds:\s*(\[[^\n]+\])/mu)?.[1];
+    if (!batchId || !selected) return { ok: false, reason: "batch_contract_missing", taskClass };
+    try {
+      const selectedRecordIds = JSON.parse(selected);
+      if (!Array.isArray(selectedRecordIds) || selectedRecordIds.length === 0) return { ok: false, reason: "batch_selection_missing", taskClass };
+    } catch { return { ok: false, reason: "batch_selection_invalid", taskClass }; }
+  }
 
   // Continuation source tasks must have an explicit, non-generic phase mapping.
   // This prevents a long-running loop from replaying an older marker forever.

tools/web/run-wbv2-supervisor.mjs

@@ -81,10 +81,12 @@ const stopOnFatal = (error, source) => {
   if (fatalHandled) return;
   fatalHandled = true;
   try {
+    failureLedger.record({ task: currentTask()?.task ?? "UNKNOWN", phase: "supervisor", reason: source, detail: error?.message ?? String(error) });
     writeCheckpoint({ state: "blocked", iteration, reason: source, error: error?.message ?? String(error) });
     appendLog(`blocked reason=${source} error=${error?.message ?? String(error)}`);
   }
   finally {
+    failureLedger.flush();
     releaseLock();
     process.exit(1);
   }