OpenAgent Graph v1.0.1

Stops the package from restating the Runtime's checkpoint policies.

graph_bootstrap, graph_continuation, graph_node_bootstrap, and
graph_node_continuation are owned by the OpenAgent Runtime's own registration
for this capability. A package policy is namespaced to plugin:graph:<tag>, so
those four entries could only ever have applied to a message this package's own
automation prints — and this package ships no automation. They changed no
message, but they did change the plugin card: the merge concatenates both
policy lists, so the installed card counted eight policies where the Runtime
applies four.

The capabilities declaration is unchanged; the merged card carries the union of
what the Runtime owns and what this package ships.

The README's validation command also could not run in this repository, which
ships no scripts. It now points at the OpenAgent Plugin Kit checkout.

No package layout change: plugin.json, README.md, LICENSE, and
skills/graph/SKILL.md, with plugin.json at the archive root.