Refactor embed handling and enhance user experience across components

- Integrated the new `buildEmbedFromPayload` function in Scheduler, Tags, and Welcome components to streamline embed creation and management.
- Updated validation schemas to require embed content checks, ensuring robust data integrity for embeds.
- Enhanced localization files to include new placeholder descriptions and improve user guidance for embed fields.
- Refactored embed parsing logic to utilize the `WelcomeEmbedSchema`, improving consistency and validation across the application.

apps/webui/src/lib/module-configs/scheduler.ts

@@ -1,4 +1,9 @@
-import type { ScheduledMessageDashboard, ScheduledMessageDashboardCreate, WelcomeEmbed } from '@nexumi/shared';
+import {
+  WelcomeEmbedSchema,
+  type ScheduledMessageDashboard,
+  type ScheduledMessageDashboardCreate,
+  type WelcomeEmbed
+} from '@nexumi/shared';
 import { Prisma, type ScheduledMessage } from '@prisma/client';
 import { prisma } from '../prisma';
 import { getScheduleQueue } from '../queues';
@@ -10,17 +15,8 @@ export class SchedulerValidationError extends Error {
 }
 
 function parseEmbed(raw: unknown): WelcomeEmbed | null {
-  if (!raw || typeof raw !== 'object' || Array.isArray(raw)) {
-    return null;
-  }
-  const record = raw as Record<string, unknown>;
-  const title = typeof record.title === 'string' ? record.title : undefined;
-  const description = typeof record.description === 'string' ? record.description : undefined;
-  const color = typeof record.color === 'number' ? record.color : undefined;
-  if (!title && !description && color === undefined) {
-    return null;
-  }
-  return { title, description, color };
+  const parsed = WelcomeEmbedSchema.safeParse(raw);
+  return parsed.success ? parsed.data : null;
 }
 
 function toDashboard(schedule: ScheduledMessage): ScheduledMessageDashboard {