feat: complete catalog fleet management workflow

backend/src/catalog/metrics.ts

@@ -0,0 +1,53 @@
+import type { CatalogMetrics } from "./types.js";
+
+export interface CatalogMetricCounts {
+  tables: number;
+  columns: number;
+  sensitiveColumns: number;
+  relationships: number;
+  describedTables: number;
+  describedColumns: number;
+}
+
+export function hasCatalogDescription(target: {
+  description: string | null;
+  generatedDescription: string | null;
+}): boolean {
+  return Boolean(target.description?.trim() || target.generatedDescription?.trim());
+}
+
+export function latestCatalogTimestamp(
+  values: readonly (string | null | undefined)[],
+): string | null {
+  let latest: number | undefined;
+  for (const value of values) {
+    if (!value) continue;
+    const timestamp = Date.parse(value);
+    if (!Number.isFinite(timestamp)) continue;
+    latest = latest === undefined ? timestamp : Math.max(latest, timestamp);
+  }
+  return latest === undefined ? null : new Date(latest).toISOString();
+}
+
+export function createCatalogMetrics(
+  databaseId: string | undefined,
+  counts: CatalogMetricCounts,
+  updatedAt: string | null,
+): CatalogMetrics {
+  const descriptionTargets = counts.tables + counts.columns;
+  const describedTargets = counts.describedTables + counts.describedColumns;
+  return {
+    scope: databaseId === undefined ? "global" : "database",
+    databaseId: databaseId ?? null,
+    tables: counts.tables,
+    columns: counts.columns,
+    sensitiveColumns: counts.sensitiveColumns,
+    relationships: counts.relationships,
+    descriptionTargets,
+    describedTargets,
+    descriptionCoverage: descriptionTargets === 0
+      ? 0
+      : Math.round((describedTargets / descriptionTargets) * 100),
+    updatedAt,
+  };
+}