[keyserver] Show the most recent thread when opening the web app with…

…out providing a thread ID

Summary:
The most recent thread can be thick and the keyserver doesn't know about it. In this case we can rely on the app to compute the `activeChatThreadID` instead of the keyserver. In `validateStateAndQueueOpsProcessing` we're handling an empty `state.navInfo.activeChatThreadID` by calling `mostRecentlyReadThreadSelector`. This means that we can simply stop handling empty `activeChatThreadID` on the keyserver side.

https://linear.app/comm/issue/ENG-9126/opening-a-link-to-the-chat-doesnt-open-the-most-recent-thick-thread

Test Plan:
Made sure that the most recent thread is thick. Opened `/webapp` and `/webapp/chat` and verified that the most recent thread is shown.
Updated the state so that a thin thread is the most recent and performed the same test.
Made sure that opening a link to a thin and to a thick thread still opens it even if it isn't the most recent.

Reviewers: kamil, inka

Reviewed By: inka

Subscribers: ashoat

Differential Revision: https://phab.comm.dev/D13590

keyserver/src/responders/redux-state-responders.js

@@ -6,7 +6,6 @@ import t, { type TInterface } from 'tcomb';
 import { baseLegalPolicies } from 'lib/facts/policies.js';
 import { daysToEntriesFromEntryInfos } from 'lib/reducers/entry-reducer.js';
 import { freshMessageStore } from 'lib/reducers/message-reducer.js';
-import { mostRecentlyReadThread } from 'lib/selectors/thread-selectors.js';
 import { mostRecentMessageTimestamp } from 'lib/shared/message-utils.js';
 import {
   threadHasPermission,
@@ -237,19 +236,13 @@ async function getInitialReduxStateResponder(
   })();
 
   const navInfoPromise = (async () => {
-    const [
-      { threadInfos },
-      messageStore,
-      currentUserInfo,
-      userInfos,
-      finalNavInfo,
-    ] = await Promise.all([
-      threadInfoPromise,
-      messageStorePromise,
-      currentUserInfoPromise,
-      userInfosPromise,
-      initialNavInfoPromise,
-    ]);
+    const [{ threadInfos }, currentUserInfo, userInfos, finalNavInfo] =
+      await Promise.all([
+        threadInfoPromise,
+        currentUserInfoPromise,
+        userInfosPromise,
+        initialNavInfoPromise,
+      ]);
 
     const requestedActiveChatThreadID = finalNavInfo.activeChatThreadID;
     if (
@@ -263,16 +256,6 @@ async function getInitialReduxStateResponder(
       finalNavInfo.activeChatThreadID = null;
     }
 
-    if (!finalNavInfo.activeChatThreadID) {
-      const mostRecentThread = mostRecentlyReadThread(
-        messageStore,
-        threadInfos,
-      );
-      if (mostRecentThread) {
-        finalNavInfo.activeChatThreadID = mostRecentThread;
-      }
-    }
-
     const curActiveChatThreadID = finalNavInfo.activeChatThreadID;
     if (
       curActiveChatThreadID &&