Added a new setting to control the width of elements based on the screen size

tools/server/webui/src/lib/components/app/chat/ChatSettings/ChatSettingsDialog.svelte

@@ -53,6 +53,11 @@
 					]
 				},
 				{
+                    key: 'responsiveChatWidth',
+                    label: 'Responsive chat width',
+                    type: 'checkbox'
+                },
+				{
 					key: 'showMessageStats',
 					label: 'Show message generation statistics',
 					type: 'checkbox'

tools/server/webui/src/lib/constants/settings-config.ts

@@ -9,6 +9,7 @@ export const SETTING_CONFIG_DEFAULT: Record<string, string | number | boolean> =
 	showToolCalls: false,
 	disableReasoningFormat: false,
 	keepStatsVisible: false,
+	responsiveChatWidth: false,
 	showMessageStats: true,
 	askForTitleConfirmation: false,
 	pasteLongTextToFileLen: 2500,
@@ -86,6 +87,8 @@ export const SETTING_CONFIG_INFO: Record<string, string> = {
 	disableReasoningFormat:
 		'Show raw LLM output without backend parsing and frontend Markdown rendering to inspect streaming across different models.',
 	keepStatsVisible: 'Keep processing statistics visible after generation finishes.',
+	responsiveChatWidth:
+		'Enable responsive chat width that adapts to your screen size. When disabled, uses a fixed width optimized for readability.',
 	showMessageStats:
 		'Display generation statistics (tokens/second, token count, duration) below each assistant message.',
 	askForTitleConfirmation: