init log using `getLog` (#7886)

src/state/messages/events/agent.ts

···
 
     try {
       const response = await networkRetry(2, () => {
-        return this.agent.api.chat.bsky.convo.listConvos(
-          {
-            limit: 1,
-          },
+        return this.agent.chat.bsky.convo.getLog(
+          {},
           {headers: DM_SERVICE_HEADERS},
         )
       })
       // throw new Error('UNCOMMENT TO TEST INIT FAILURE')
 
-      const {convos} = response.data
+      const {cursor} = response.data
 
-      for (const convo of convos) {
-        if (convo.rev > (this.latestRev = this.latestRev || convo.rev)) {
-          this.latestRev = convo.rev
+      // should always be defined
+      if (cursor) {
+        if (!this.latestRev) {
+          this.latestRev = cursor
+        } else if (cursor > this.latestRev) {
+          this.latestRev = cursor
         }
       }