🤖 feat: Gemini 1.5 Support (+Vertex AI) (#2383)

* WIP: gemini-1.5 support

* feat: extended vertex ai support

* fix: handle possibly undefined modelName

* fix: gpt-4-turbo-preview invalid vision model

* feat: specify `fileConfig.imageOutputType` and make PNG default image conversion type

* feat: better truncation for errors including base64 strings

* fix: gemini inlineData formatting

* feat: RAG augmented prompt for gemini-1.5

* feat: gemini-1.5 rates and token window

* chore: adjust tokens, update docs, update vision Models

* chore: add back `ChatGoogleVertexAI` for chat models via vertex ai

* refactor: ask/edit controllers to not use `unfinished` field for google endpoint

* chore: remove comment

* chore(ci): fix AppService test

* chore: remove comment

* refactor(GoogleSearch): use `GOOGLE_SEARCH_API_KEY` instead, issue warning for old variable

* chore: bump data-provider to 0.5.4

* chore: update docs

* fix: condition for gemini-1.5 using generative ai lib

* chore: update docs

* ci: add additional AppService test for `imageOutputType`

* refactor: optimize new config value `imageOutputType`

* chore: bump CONFIG_VERSION

* fix(assistants): avatar upload

docs/install/configuration/custom_config.md

@@ -209,6 +209,13 @@ This example configuration file sets up LibreChat with detailed options across s
 - **Description**: Whether or not to secure access to image links that are hosted locally by the app. Default: false.
 - **Example**: `secureImageLinks: true`
 
+### Image Output Type
+- **Key**: `imageOutputType`
+- **Type**: String, "png" | "webp" | "jpeg"
+- **Description**: The image output type for image responses. Defaults to "png" if omitted.
+- **Note**: Case-sensitive. Google endpoint only supports "jpeg" and "png" output types.
+- **Example**: `imageOutputType: "webp"`
+
 ### File Configuration
 - **Key**: `fileConfig`
 - **Type**: Object