feat: gate session cleanup by runtime capabilities

src/shared/capabilities.ts

@@ -0,0 +1,32 @@
+import { PI_WEB_CAPABILITIES, type PiWebCapability, type PiWebRuntimeComponent, type PiWebServiceComponent } from "./apiTypes.js";
+
+export { PI_WEB_CAPABILITIES };
+export type { PiWebCapability };
+
+export const KNOWN_PI_WEB_CAPABILITIES = Object.values(PI_WEB_CAPABILITIES);
+const knownPiWebCapabilities: ReadonlySet<string> = new Set(KNOWN_PI_WEB_CAPABILITIES);
+
+export const WEB_RUNTIME_CAPABILITIES = [PI_WEB_CAPABILITIES.sessionsDeleteArchived] as const satisfies readonly PiWebCapability[];
+export const SESSIOND_RUNTIME_CAPABILITIES = [PI_WEB_CAPABILITIES.sessionsDeleteArchived] as const satisfies readonly PiWebCapability[];
+
+const EFFECTIVE_CAPABILITY_REQUIREMENTS = {
+  [PI_WEB_CAPABILITIES.sessionsDeleteArchived]: ["web", "sessiond"],
+} as const satisfies Record<PiWebCapability, readonly PiWebServiceComponent[]>;
+
+export function isPiWebCapability(value: unknown): value is PiWebCapability {
+  return typeof value === "string" && knownPiWebCapabilities.has(value);
+}
+
+export function supportsPiWebCapability(source: { capabilities?: readonly PiWebCapability[] } | undefined, capability: PiWebCapability): boolean {
+  return source?.capabilities?.includes(capability) === true;
+}
+
+export function effectivePiWebCapabilities(components: Partial<Record<PiWebServiceComponent, Pick<PiWebRuntimeComponent, "available" | "capabilities">>>): PiWebCapability[] {
+  return KNOWN_PI_WEB_CAPABILITIES.filter((capability) => {
+    const requiredComponents = EFFECTIVE_CAPABILITY_REQUIREMENTS[capability];
+    return requiredComponents.every((component) => {
+      const runtime = components[component];
+      return runtime?.available === true && supportsPiWebCapability(runtime, capability);
+    });
+  });
+}