🧹fix: Handle Abort Message Edge Cases (#1462)

* chore: bump langchain to v0.0.213 from v0.0.186

* fix: handle abort edge cases:
- abort message server-side if response experienced error mid-generation
- attempt to recover message if aborting resulted in error
- if abortKey is not provided, use conversationId if it exists
- if headers were already sent, send an Event stream message
- issue warning for possible Google censor/filter

refactor(streamResponse): for `sendError`, allow passing overrides so that error can include partial generation, improve typing for `sendMessage`

* chore(MessageContent): remove eslint warning for unused `i`, rephrase unfinished message text

* fix(useSSE): avoid invoking cancelHandler if the abort response was 404

* chore(TMessage): remove unnecessary, unused legacy message property `submitting`

* chore(TMessage): remove unnecessary legacy message property `cancelled`

* chore(abortMiddleware): remove unused `errorText` property to avoid confusion

api/server/routes/ask/askChatGPTBrowser.js

@@ -99,7 +99,6 @@ const ask = async ({
             parentMessageId: overrideParentMessageId || userMessageId,
             text: text,
             unfinished: true,
-            cancelled: false,
             error: false,
             isCreatedByUser: false,
             user,
@@ -155,7 +154,6 @@ const ask = async ({
       text: await handleText(response),
       sender: endpointOption?.chatGptLabel || 'ChatGPT',
       unfinished: false,
-      cancelled: false,
       error: false,
       isCreatedByUser: false,
     };
@@ -226,7 +224,6 @@ const ask = async ({
       conversationId,
       parentMessageId: overrideParentMessageId || userMessageId,
       unfinished: false,
-      cancelled: false,
       error: true,
       isCreatedByUser: false,
       text: `${getPartialMessage() ?? ''}\n\nError message: "${error.message}"`,