Retain host and server scope during investigations

src/lib/hosts.ts

@@ -113,6 +113,15 @@ export interface HostOperationSummary extends Omit<HostOperation, 'payload' | 'r
     routine: boolean;
 }
 export type HostOperationFilter = 'important' | 'routine' | 'all';
+export interface HostOperationScope { host?: string; server?: string }
+export function hostOperationScope(params: URLSearchParams): HostOperationScope {
+    const scope: HostOperationScope = {};
+    for (const key of ['host', 'server'] as const) {
+        const value = params.get(key);
+        if (value && value.length <= 512 && !/[\x00-\x1f\x7f]/.test(value)) scope[key] = value;
+    }
+    return scope;
+}
 export function isHostOperationFilter(value: unknown): value is HostOperationFilter {
     return typeof value === 'string' && ['important', 'routine', 'all'].includes(value);
 }