feat(home): animated typewriter placeholder for the prompt composer

Cycle through localized example prompts with a typing/deleting animation
in the home composer placeholder, start the field empty instead of with
a default prompt, and style the home editor with larger prompt text.

Also rebrand the device-management copy from Lovart to Moteva.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

frontend/src/i18n/i18n.tsx

@@ -29,7 +29,7 @@ const dictionaries: Record<Locale, Dictionary> = {
     email: "电子邮箱",
     deviceManagement: "设备管理",
     removeAllDevices: "移除全部设备",
-    removeAllDevicesDescription: "Lovart 账户仅限个人使用。为防止滥用并确保平台稳定，任务最多可同时在 2 个桌面 Web 会话和 1 个移动 Web 会话中运行。如需团队或多人使用，请购买 Team Plan。",
+    removeAllDevicesDescription: "Moteva 账户仅限个人使用。为防止滥用并确保平台稳定，任务最多可同时在 2 个桌面 Web 会话和 1 个移动 Web 会话中运行。如需团队或多人使用，请购买 Team Plan。",
     onlineStatus: "在线状态",
     deviceInfo: "设备信息",
     currentDevice: "当前设备",
@@ -490,7 +490,7 @@ const dictionaries: Record<Locale, Dictionary> = {
     email: "Email",
     deviceManagement: "Device Management",
     removeAllDevices: "Remove All Devices",
-    removeAllDevicesDescription: "A Lovart account is for personal use only. To prevent abuse and keep the platform stable, tasks can run in up to 2 desktop web sessions and 1 mobile web session at the same time. For team or multi-person use, please purchase Team Plan.",
+    removeAllDevicesDescription: "A Moteva account is for personal use only. To prevent abuse and keep the platform stable, tasks can run in up to 2 desktop web sessions and 1 mobile web session at the same time. For team or multi-person use, please purchase Team Plan.",
     onlineStatus: "Online",
     deviceInfo: "Device Info",
     currentDevice: "Current Device",