refactor(admin): split multi-tenant page.tsx into colocated components

Extract types, constants, helpers, and UI pieces (LoadingSkeleton,
EmptyState, StatCard, ComplianceRing, Modal, TenantCard,
CreateTenantModal, EditTenantModal, TenantDetailModal) into
_components/ and _types.ts to bring page.tsx from 1663 LOC to
432 LOC (under the 500 hard cap). Behavior preserved.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

admin-compliance/app/sdk/multi-tenant/_components/ComplianceRing.tsx

@@ -0,0 +1,42 @@
+'use client'
+
+import { getScoreColor } from './helpers'
+
+export function ComplianceRing({ score, size = 64 }: { score: number; size?: number }) {
+  const strokeWidth = 5
+  const radius = (size - strokeWidth) / 2
+  const circumference = 2 * Math.PI * radius
+  const progress = Math.max(0, Math.min(100, score))
+  const offset = circumference - (progress / 100) * circumference
+  const color = getScoreColor(score)
+
+  return (
+    <div className="relative" style={{ width: size, height: size }}>
+      <svg width={size} height={size} className="transform -rotate-90">
+        <circle
+          cx={size / 2}
+          cy={size / 2}
+          r={radius}
+          fill="none"
+          stroke="#e2e8f0"
+          strokeWidth={strokeWidth}
+        />
+        <circle
+          cx={size / 2}
+          cy={size / 2}
+          r={radius}
+          fill="none"
+          stroke={color}
+          strokeWidth={strokeWidth}
+          strokeDasharray={circumference}
+          strokeDashoffset={offset}
+          strokeLinecap="round"
+          className="transition-all duration-700 ease-out"
+        />
+      </svg>
+      <div className="absolute inset-0 flex items-center justify-center">
+        <span className="text-sm font-bold text-slate-900">{score}</span>
+      </div>
+    </div>
+  )
+}