Fix race condition where streamed events could be lost

Events stream in via model_write listener while also being fetched
from the database. If the DB fetch completed before all events were
persisted, replaceModelsInStore would wipe out events that came in
via model_write.

Added mergeModelsInStore that adds fetched events without removing
existing ones. Applied to HTTP, gRPC, and WebSocket event hooks.

src-web/hooks/useHttpResponseEvents.ts

@@ -1,6 +1,10 @@
 import { invoke } from '@tauri-apps/api/core';
 import type { HttpResponse, HttpResponseEvent } from '@yaakapp-internal/models';
-import { httpResponseEventsAtom, replaceModelsInStore } from '@yaakapp-internal/models';
+import {
+  httpResponseEventsAtom,
+  mergeModelsInStore,
+  replaceModelsInStore,
+} from '@yaakapp-internal/models';
 import { useAtomValue } from 'jotai';
 import { useEffect, useMemo } from 'react';
 
@@ -13,8 +17,10 @@ export function useHttpResponseEvents(response: HttpResponse | null) {
       return;
     }
 
+    // Use merge instead of replace to preserve events that came in via model_write
+    // while we were fetching from the database
     invoke<HttpResponseEvent[]>('cmd_get_http_response_events', { responseId: response.id }).then(
-      (events) => replaceModelsInStore('http_response_event', events),
+      (events) => mergeModelsInStore('http_response_event', events),
     );
   }, [response?.id]);