feat: consolidate database management work

Add catalog-owned logical relationships and runtime snapshots, extend the database-management UI and validation coverage, and document the updated operational workflow.

Keep active sensitive-generation status in a tooltip and indicator, and update the layout E2E to follow the history action in its new database-scoped location.

backend/test/catalog-tables-routes.test.ts

@@ -54,6 +54,7 @@ async function setup() {
     list: vi.fn(async () => [revision]),
     listCatalog: vi.fn(async () => [{ id: "psd-clinical", name: "Policlinico San Donato", configurationState: "ready", revision }]),
     read: vi.fn(async () => ({ workspace, revision })),
+    readPinned: vi.fn(async () => ({ workspace, workspaceConfigPath: revision.snapshotPath })),
   } as unknown as WorkspaceRegistry;
   const secretStore = new WorkspaceSecretStore({ root: secretRoot, runtimeRoot, installationId: "test" });
   const app = buildApp(loadConfig({ THT_HARNESS_DIR: "/missing", NODE_ENV: "test" }), {