Add pnpm Ecosystem Protections

These are some excellent options from pnpm to prevent some kinds of
threats against the ecosystem. Let's apply them.

Author: jrjohnson

pnpm-lock.yaml

@@ -0,0 +1,4 @@
+# Protect against package ecosystem threats
+minimumReleaseAge: 1440 # only install things that are at least one day old
+trustPolicy: no-downgrade # never install anything where the publication provenance is less than it was
+blockExoticSubdeps: true # block installing things not from the registry