feat(blocks): add context-driven global search

Add a command-style global search dialog with asynchronous cancellation, paginated grouped results, highlighting, loading and error states, recent query history, and a configurable Mod+K shortcut.

Make search sources and result actions host-defined through SearchProvider and SearchAdapter, so the block has no route, database, or HTTP dependency. Export the block, register i18n discovery, and cover adapter pagination and selection behavior.

packages/ui/src/components/dialog.tsx

@@ -14,11 +14,15 @@ function createDialogHandle<Payload>(): DialogHandle<Payload> {
   return DialogPrimitive.createHandle<Payload>()
 }
 
-function Dialog({ ...props }: DialogPrimitive.Root.Props) {
+function Dialog<Payload = unknown>({
+  ...props
+}: DialogPrimitive.Root.Props<Payload>) {
   return <DialogPrimitive.Root data-slot="dialog" {...props} />
 }
 
-function DialogTrigger({ ...props }: DialogPrimitive.Trigger.Props) {
+function DialogTrigger<Payload = unknown>({
+  ...props
+}: DialogPrimitive.Trigger.Props<Payload>) {
   return <DialogPrimitive.Trigger data-slot="dialog-trigger" {...props} />
 }