Switch UI components to new design system tokens

Standardizes color values and styling using the new tokens:
- Replaces hardcoded colors with semantic variables
- Updates background/text/border classes for light/dark mode
- Migrates inputs to UInput/USelect/UTextarea components
- Removes redundant style declarations

server/models/event.js

@@ -2,7 +2,7 @@ import mongoose from "mongoose";
 
 const eventSchema = new mongoose.Schema({
   title: { type: String, required: true },
-  slug: { type: String, required: true, unique: true },
+  slug: { type: String, unique: true }, // Auto-generated in pre-save hook
   tagline: String,
   description: { type: String, required: true },
   content: String,
@@ -133,7 +133,8 @@ function generateSlug(title) {
 // Pre-save hook to generate slug
 eventSchema.pre("save", async function (next) {
   try {
-    if (this.isNew || this.isModified("title")) {
+    // Always generate slug if it doesn't exist or if title has changed
+    if (!this.slug || this.isNew || this.isModified("title")) {
       let baseSlug = generateSlug(this.title);
       let slug = baseSlug;
       let counter = 1;