m/node/allocs: split new package off m/node

The metropolis/node package contains various unrelated things. One of
these things are node-wide allocations of identifiers.
These are moved here to the new metropolis/node/allocs package.
Additionally, the constants are renamed to move the type of identifier
in front.

Change-Id: Ibc841ca64d4450a7054463e6d2d44753a118e07a
Reviewed-on: https://review.monogon.dev/c/monogon/+/4566
Reviewed-by: Tim Windelschmidt <tim@monogon.tech>
Tested-by: Jenkins CI
diff --git a/metropolis/node/core/metrics/BUILD.bazel b/metropolis/node/core/metrics/BUILD.bazel
index bc94863..861d59f 100644
--- a/metropolis/node/core/metrics/BUILD.bazel
+++ b/metropolis/node/core/metrics/BUILD.bazel
@@ -11,7 +11,7 @@
     visibility = ["//visibility:public"],
     deps = [
         "//go/types/mapsets",
-        "//metropolis/node",
+        "//metropolis/node/allocs",
         "//metropolis/node/core/curator/proto/api",
         "//metropolis/node/core/curator/watcher",
         "//metropolis/node/core/identity",
@@ -32,7 +32,7 @@
         "xFakeExporterPath": "$(rlocationpath //metropolis/node/core/metrics/fake_exporter )",
     },
     deps = [
-        "//metropolis/node",
+        "//metropolis/node/allocs",
         "//metropolis/node/core/curator/proto/api",
         "//metropolis/test/util",
         "//osbase/supervisor",