chore: import upstream snapshot with attribution

apps/sim/blocks/visibility/server-context.ts

@@ -0,0 +1,25 @@
+import { AsyncLocalStorage } from 'node:async_hooks'
+import type { BlockVisibilityState } from '@/lib/core/config/block-visibility'
+import { registerBlockVisibilityResolver } from '@/blocks/visibility/context'
+
+/**
+ * Server-side visibility context: a per-request AsyncLocalStorage, independent
+ * of the custom-block overlay's ALS so `withBlockVisibility` and
+ * `withCustomBlockOverlay` nest in either order without clobbering each other.
+ *
+ * Only copilot/mothership discovery paths establish this scope. Execution entry
+ * points (execute route, trigger.dev tasks, schedules/webhooks) never do — so
+ * placed preview blocks always serialize and run, and `preview` blocks stay
+ * hidden on unscoped discovery reads purely via the static fail-closed default.
+ */
+const store = new AsyncLocalStorage<BlockVisibilityState>()
+
+registerBlockVisibilityResolver({ current: () => store.getStore() ?? null })
+
+/** Run `fn` with the given visibility state resolvable via the registry accessors. */
+export function withBlockVisibility<T>(
+  vis: BlockVisibilityState,
+  fn: () => Promise<T>
+): Promise<T> {
+  return store.run(vis, fn)
+}