🗓️ feat: Add Special Variables for Prompts & Agents, Prompt UI Improvements (#7123)

* wip: Add Instructions component for agent configuration

* ✨ feat: Implement DropdownPopup for variable insertion in instructions

* refactor: Enhance variable handling by exporting specialVariables and updating Markdown components

* feat: Add special variable support for current date and user in Instructions component

* refactor: Update handleAddVariable to include localized label

* feat: replace special variables in instructions presets

* chore: update parameter type for user in getListAgents function

* refactor: integrate dayjs for date handling and move replaceSpecialVars function to data-provider

* feat: enhance replaceSpecialVars to include day number in current date format

* feat: integrate replaceSpecialVars for processing agent instructions

* feat: add support for current date & time in replaceSpecialVars function

* feat: add iso_datetime support in replaceSpecialVars function

* fix: enforce text parameter to be a required field in replaceSpecialVars function

* feat: add ISO datetime support in translation file

* fix: disable eslint warning for autoFocus in TextareaAutosize component

* feat: add VariablesDropdown component and integrate it into CreatePromptForm and PromptEditor; update translation for special variables

* fix: CategorySelector and related localizations

* fix: add z-index class to LanguageSTTDropdown for proper stacking context

* fix: add max-height and overflow styles to OGDialogContent in VariableDialog and PreviewPrompt components

* fix: update variable detection logic to exclude special variables and improve regex matching

* fix: improve accessibility text for actions menu in ChatGroupItem component

* fix: adjust max-width and height styles for dialog components and improve markdown rendering for light vs. dark, height/widths, etc.

* fix: remove commented-out code for better readability in PromptVariableGfm component

* fix: handle undefined input parameter in setParams function call

* fix: update variable label types to use TSpecialVarLabel for consistency

* fix: remove outdated information from special variables description in translation file

* fix: enhance unused i18next keys detection for special variable keys

* fix: update color classes for consistency/a11y in category and prompt variable components

* fix: update PromptVariableGfm component and special variable styles for consistency

* fix: improve variable highlighting logic in VariableForm component

* fix: update background color classes for consistency in VariableForm component

* fix: add missing ref parameter to Dialog component in OriginalDialog

* refactor: move navigate call for new conversation to after setConversation update

* refactor: move message query hook to client workspace; fix: handle edge case for navigation from finalHandler creating race condition for response message DB save

* chore: bump librechat-data-provider to 0.7.793

* ci: add unit tests for replaceSpecialVars function

* fix: implement getToolkitKey function for image_gen_oai toolkit filtering/including

* ci: enhance dayjs mock for consistent date/time values in tests

* fix: MCP stdio server fail to start when passing env property

* fix: use optional chaining for clientRef dereferencing in AskController and EditController
feat: add context to saveMessage call in streamResponse utility

* fix: only save error messages if the userMessageId was initialized

* refactor: add isNotAppendable check to disable inputs in ChatForm and useTextarea

* feat: enhance error handling in useEventHandlers and update conversation state in useNewConvo

* refactor: prepend underscore to conversationId in newConversation template

* feat: log aborted conversations with minimal messages and use consistent conversationId generation

---------

Co-authored-by: Olivier Schiavo <olivier.schiavo@wengo.com>
Co-authored-by: aka012 <aka012@neowiz.com>
Co-authored-by: jiasheng <jiashengguo@outlook.com>

client/src/components/Prompts/Groups/CreatePromptForm.tsx

@@ -7,6 +7,7 @@ import PromptVariables from '~/components/Prompts/PromptVariables';
 import { Button, TextareaAutosize, Input } from '~/components/ui';
 import Description from '~/components/Prompts/Description';
 import { useLocalize, useHasAccess } from '~/hooks';
+import VariablesDropdown from '~/components/Prompts/VariablesDropdown';
 import Command from '~/components/Prompts/Command';
 import { useCreatePrompt } from '~/data-provider';
 import { cn } from '~/utils';
@@ -132,7 +133,8 @@ const CreatePromptForm = ({
         <div className="flex w-full flex-col gap-4 md:mt-[1.075rem]">
           <div>
             <h2 className="flex items-center justify-between rounded-t-lg border border-border-medium py-2 pl-4 pr-1 text-base font-semibold dark:text-gray-200">
-              {localize('com_ui_prompt_text')}*
+              <span>{localize('com_ui_prompt_text')}*</span>
+              <VariablesDropdown fieldName="prompt" className="mr-2" />
             </h2>
             <div className="min-h-32 rounded-b-lg border border-border-medium p-4 transition-all duration-150">
               <Controller