fix: Enhance Test Coverage and Fix Compatibility Issues 👷‍♂️ (#1363)

* refactor: only remove conversation states from localStorage on login/logout but not on refresh

* chore: add debugging log for azure completion url

* chore: add api-key to redact regex

* fix: do not show endpoint selector if endpoint is falsy

* chore: remove logger from genAzureChatCompletion

* feat(ci): mock fetchEventSource

* refactor(ci): mock all model methods in BaseClient.test, as well as mock the implementation for getCompletion in FakeClient

* fix(OpenAIClient): consider chatCompletion if model name includes `gpt` as opposed to `gpt-`

* fix(ChatGPTClient/azureOpenAI): Remove 'model' option for Azure compatibility (cannot be sent in payload body)

* feat(ci): write new test suite that significantly increase test coverage for OpenAIClient and BaseClient by covering most of the real implementation of the `sendMessage` method
- test for the azure edge case where model option is appended to modelOptions, ensuring removal before sent to the azure endpoint
- test for expected azure url being passed to SSE POST request
- test for AZURE_OPENAI_DEFAULT_MODEL being set, but is not included in the URL deployment name as expected
- test getCompletion method to have correct payload
fix(ci/OpenAIClient.test.js): correctly mock hanging/async methods

* refactor(addTitle): allow azure to title as it aborts signal on completion

api/app/clients/specs/FakeClient.js

@@ -42,7 +42,6 @@ class FakeClient extends BaseClient {
 
     this.maxContextTokens = getModelMaxTokens(this.modelOptions.model) ?? 4097;
   }
-  getCompletion() {}
   buildMessages() {}
   getTokenCount(str) {
     return str.length;
@@ -86,6 +85,19 @@ const initializeFakeClient = (apiKey, options, fakeMessages) => {
     return 'Mock response text';
   });
 
+  // eslint-disable-next-line no-unused-vars
+  TestClient.getCompletion = jest.fn().mockImplementation(async (..._args) => {
+    return {
+      choices: [
+        {
+          message: {
+            content: 'Mock response text',
+          },
+        },
+      ],
+    };
+  });
+
   TestClient.buildMessages = jest.fn(async (messages, parentMessageId) => {
     const orderedMessages = TestClient.constructor.getMessagesForConversation({
       messages,