p2.7: prometheus /metrics

Default GET /metrics is Prometheus text; JSON stays at /metrics.json
and ?format=json. :8443 needs the metrics caller bearer; loopback
stays open. Restricted callers have no per-caller series and no
tavily:restricted gauge.

vendor/google.golang.org/protobuf/internal/impl/codec_unsafe.go

@@ -0,0 +1,15 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package impl
+
+// When using unsafe pointers, we can just treat enum values as int32s.
+
+var (
+	coderEnumNoZero      = coderInt32NoZero
+	coderEnum            = coderInt32
+	coderEnumPtr         = coderInt32Ptr
+	coderEnumSlice       = coderInt32Slice
+	coderEnumPackedSlice = coderInt32PackedSlice
+)