feat(webapp): surface buffered state in admin-only details for run detail panel

Admins triaging a run from the dashboard need a single-glance answer to
"is this row in PG yet or sitting in the mollifier buffer?". The
existing Admin only section already carries Worker queue / Trace ID /
Span ID / Task event store; add a Buffered yes/no field at the top
of the same block. Gates off the `isBuffered` flag already on
SpanRun (`false` on the PG branch, `true` on the buffered synth).

No customer-facing change — only renders when `useHasAdminAccess()` is
true.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: d-cs

apps/webapp/app/routes/resources.orgs.$organizationSlug.projects.$projectParam.env.$envParam.runs.$runParam.spans.$spanParam/route.tsx

@@ -1022,6 +1022,10 @@ function RunBody({
                     <Paragraph spacing variant="small" className="text-yellow-500">
                       Admin only
                     </Paragraph>
+                    <Property.Item>
+                      <Property.Label>Buffered</Property.Label>
+                      <Property.Value>{run.isBuffered ? "Yes" : "No"}</Property.Value>
+                    </Property.Item>
                     <Property.Item>
                       <Property.Label>Worker queue</Property.Label>
                       <Property.Value>{run.workerQueue}</Property.Value>