style(workflows): stack the lane pipeline and skill usage panels

Both panels carry wide tables that were fighting for half a row on lg
screens. Each gets its own full-width row instead.

client/src/pages/Workflows.tsx

@@ -205,12 +205,12 @@ export function Workflows() {
       {/* Stats Row */}
       <WorkflowStats stats={data.stats} />
 
-      {/* Section 1 + 2: this dashboard's own pipelines, and what drives them */}
+      {/* Section 1: this dashboard's own pipelines */}
-      <div className="grid grid-cols-1 lg:grid-cols-2 gap-6">
       <Section number={1} title={t("lanes.title")} subtitle={t("lanes.subtitle")} infoKey="lanes">
         <LanePipelinePanel />
       </Section>
 
+      {/* Section 2: what drives those pipelines */}
       <Section
         number={2}
         title={t("skillUsage.title")}
@@ -219,7 +219,6 @@ export function Workflows() {
       >
         <SkillUsagePanel statusFilter={statusFilter} />
       </Section>
-      </div>
 
       {/* Workflow-tool runs (issue #167) - fleets ingested from on-disk journals */}
       <div className="card p-4 space-y-3">

client/src/pages/__tests__/__snapshots__/screens.snapshot.test.tsx.snap

@@ -10350,9 +10350,6 @@ exports[`screen snapshots > Workflows 1`] = `
         </div>
       </div>
     </div>
-    <div
-      class="grid grid-cols-1 lg:grid-cols-2 gap-6"
-    >
     <div
       class="flex flex-col h-full"
     >
@@ -10497,7 +10494,6 @@ exports[`screen snapshots > Workflows 1`] = `
         </p>
       </div>
     </div>
-    </div>
     <div
       class="card p-4 space-y-3"
     >