Register a new module from the builder's first done key and ask no first build; its condition reads the key and names a manifest word this controller does not read (issue 1851, A5a, A5b)

internal/builderkeys/builderkeys.go

@@ -158,6 +158,39 @@ func (r Reader) ModuleAt(ctx context.Context, module, commit string) (delivery.M
 	return pickAt(module, commit, values)
 }
 
+// Modules is every module the indexer holds a trunk value of, by module: the value it holds now. A value that does not
+// decode is left out and said in unread.
+func (r Reader) Modules(ctx context.Context) (values map[string]delivery.Module, unread map[string]error, err error) {
+	kv, err := r.bucket(ctx, delivery.ModulesBucket)
+	if err != nil || kv == nil {
+		return nil, nil, err
+	}
+	keys, err := kv.Keys(ctx)
+	if errors.Is(err, jetstream.ErrNoKeysFound) {
+		return nil, nil, nil
+	}
+	if err != nil {
+		return nil, nil, fmt.Errorf("listing the indexer's modules: %w", err)
+	}
+	values, unread = map[string]delivery.Module{}, map[string]error{}
+	for _, key := range keys {
+		e, err := kv.Get(ctx, key)
+		if errors.Is(err, jetstream.ErrKeyNotFound) {
+			continue
+		}
+		if err != nil {
+			return nil, nil, fmt.Errorf("the indexer's value of %s: %w", key, err)
+		}
+		m, err := delivery.DecodeModule(e.Value())
+		if err != nil {
+			unread[key] = err
+			continue
+		}
+		values[key] = m
+	}
+	return values, unread, nil
+}
+
 // pickAt is, of a key's values oldest first, the newest whose commit is commit (any, with commit empty); values that
 // do not decode are passed over, and one of them is said when nothing else is found.
 func pickAt(module, commit string, values [][]byte) (delivery.Module, error) {