Emit live hook prompts before raw-event filtering (#17189)

# What
Project raw Stop-hook prompt response items into typed v2 hookPrompt
item-completed notifications before applying the raw-response-event
filter. Keep ordinary raw response items filtered for normal
subscribers; only the existing hookPrompt bridge runs on the filtered
raw-item path.

# Why
Blocked Stop hooks record their continuation instruction as a raw
model-history user item. Normal v2 desktop subscribers do not opt into
raw response events, so the app-server listener filtered that raw item
before the existing hookPrompt translator could emit the typed live
item/completed notification. As a result, the hook-prompt bubble only
appeared after thread history was reloaded.

codex-rs/app-server/src/bespoke_event_handling.rs

@@ -2059,7 +2059,7 @@ async fn maybe_emit_raw_response_item_completed(
         .await;
 }
 
-async fn maybe_emit_hook_prompt_item_completed(
+pub(crate) async fn maybe_emit_hook_prompt_item_completed(
     api_version: ApiVersion,
     conversation_id: ThreadId,
     turn_id: &str,