fix: 6 bugs (timeline path value, seer SSE cursor, erasure checksum, subtle compare, build status code, dead WorkerName branch)

internal/erasure/service.go

@@ -176,12 +176,12 @@ func (s *Service) Reconstruct(ctx context.Context, bundleID string, indices []in
 	for i := 0; i < bundle.DataShards; i++ {
 		out = append(out, shards[i]...)
 	}
-	// Trim padding — find actual length via checksum match
-	sum := sha256.Sum256(out)
+	trimmed := trimNullPadding(out)
+	sum := sha256.Sum256(trimmed)
 	if hex.EncodeToString(sum[:]) != bundle.Checksum {
-		// Return best-effort; caller validates
+		return nil, fmt.Errorf("reconstructed data checksum mismatch: bundle may be corrupt")
 	}
-	return trimNullPadding(out), nil
+	return trimmed, nil
 }
 
 func trimNullPadding(b []byte) []byte {