🌎 i18n: React-i18next & i18next Integration (#5720)

* better i18n support an internationalization-framework.

* removed unused package

* auto sort for translation.json

* fixed tests with the new locales function

* added new CI actions from locize

* to use locize a mention in the README.md

* to use locize a mention in the README.md

* updated README.md and added TRANSLATION.md to the repo

* updated TRANSLATION.md badges

* updated README.md to go to the TRANSLATION.md when clicking on the Translation Progress badge

* updated TRANSLATION.md and added a new issue template.

* updated TRANSLATION.md and added a new issue template.

* updated issue template to add the iso code link.

* updated the new GitHub actions for `locize`

* updated label for new issue template --> i18n

* fixed type issue

* Fix eslint

* Fix eslint with key-spacing spacing

* fix: error type

* fix: handle undefined values in SortFilterHeader component

* fix: typing in Image component

* fix: handle optional promptGroup in PromptCard component

* fix: update localize function to accept string type and remove unnecessary JSX element

* fix: update localize function to enforce TranslationKeys type for better type safety

* fix: improve type safety and handle null values in Assistants component

* fix: enhance null checks for fileId in FilesListView component

* fix: localize 'Go back' button text in FilesListView component

* fix: update aria-label for menu buttons and add translation for 'Close Menu'

* docs: add Reasoning UI section for Chain-of-Thought AI models in README

* fix: enhance type safety by adding type for message in MultiMessage component

* fix: improve null checks and optional chaining in useAutoSave hook

* fix: improve handling of optional properties in cleanupPreset function

* fix: ensure isFetchingNextPage defaults to false and improve null checks for messages in Search component

* fix: enhance type safety and null checks in useBuildMessageTree hook

---------

Co-authored-by: Danny Avila <danny@librechat.ai>

client/src/components/SidePanel/Agents/AgentAvatar.tsx

@@ -171,7 +171,7 @@ function Avatar({
     } else {
       const megabytes = sizeLimit ? formatBytes(sizeLimit) : 2;
       showToast({
-        message: localize('com_ui_upload_invalid_var', megabytes + ''),
+        message: localize('com_ui_upload_invalid_var', { 0: megabytes + '' }),
         status: 'error',
       });
     }

client/src/components/SidePanel/Agents/FileSearchCheckbox.tsx

@@ -38,7 +38,7 @@ export default function FileSearchCheckbox() {
             type="button"
             className="flex items-center space-x-2"
             onClick={() =>
-              // eslint-disable-next-line @typescript-eslint/strict-boolean-expressions
+
               setValue(AgentCapabilities.file_search, !getValues(AgentCapabilities.file_search), {
                 shouldDirty: true,
               })

client/src/components/SidePanel/Agents/ImageVision.tsx

@@ -20,7 +20,7 @@ export default function ImageVision() {
             checked={field.value}
             onCheckedChange={field.onChange}
             className="relative float-left  mr-2 inline-flex h-4 w-4 cursor-pointer"
-            value={field?.value?.toString()}
+            value={field.value?.toString()}
           />
         )}
       />

client/src/components/SidePanel/Agents/ModelPanel.tsx

@@ -222,7 +222,7 @@ export default function Parameters({
               className="btn btn-neutral flex w-full items-center justify-center gap-2 px-4 py-2 text-sm"
             >
               <RotateCcw className="h-4 w-4" aria-hidden="true" />
-              {localize('com_ui_reset_var', localize('com_ui_model_parameters'))}
+              {localize('com_ui_reset_var', { 0: localize('com_ui_model_parameters') })}
             </button>
           </div>
         </div>

client/src/components/SidePanel/Agents/Retrieval.tsx

@@ -43,7 +43,7 @@ export default function Retrieval({ retrievalModels }: { retrievalModels: Set<st
                 disabled={isDisabled}
                 onCheckedChange={field.onChange}
                 className="relative float-left mr-2 inline-flex h-4 w-4 cursor-pointer"
-                value={field?.value?.toString()}
+                value={field.value?.toString()}
               />
             )}
           />

client/src/components/SidePanel/Agents/Sequential/HideSequential.tsx

@@ -38,7 +38,7 @@ export default function HideSequential() {
             type="button"
             className="flex items-center space-x-2"
             onClick={() =>
-              // eslint-disable-next-line @typescript-eslint/strict-boolean-expressions
+
               setValue(
                 AgentCapabilities.hide_sequential_outputs,
                 !getValues(AgentCapabilities.hide_sequential_outputs),

client/src/components/SidePanel/Agents/ShareAgent.tsx

@@ -137,7 +137,7 @@ export default function ShareAgent({
           )}
           aria-label={localize(
             'com_ui_share_var',
-            agentName != null && agentName !== '' ? `"${agentName}"` : localize('com_ui_agent'),
+            { 0: agentName != null && agentName !== '' ? `"${agentName}"` : localize('com_ui_agent') },
           )}
           type="button"
         >
@@ -150,7 +150,7 @@ export default function ShareAgent({
         <OGDialogTitle>
           {localize(
             'com_ui_share_var',
-            agentName != null && agentName !== '' ? `"${agentName}"` : localize('com_ui_agent'),
+            { 0: agentName != null && agentName !== '' ? `"${agentName}"` : localize('com_ui_agent') },
           )}
         </OGDialogTitle>
         <form