Add PostgreSQL support with SQLite/Postgres database compatibility layer

- Add dbGet/dbAll helper functions for database-agnostic queries
- Add toDbBool/convertBooleansForDb for boolean type conversion
- Add toDbDate/getNow for timestamp type handling
- Add generateId that returns UUID for Postgres, nanoid for SQLite
- Update all routes to use compatibility helpers
- Add normalizeEvent to return clean number types from Postgres decimal
- Add formatPrice utility for consistent price display
- Add legal pages admin interface with RichTextEditor
- Update carousel images
- Add drizzle migration files for PostgreSQL

backend/src/lib/utils.ts

@@ -1,15 +1,71 @@
 import { nanoid } from 'nanoid';
+import { randomUUID } from 'crypto';
 
+/**
+ * Get database type (reads env var each time to handle module loading order)
+ */
+function getDbType(): string {
+  return process.env.DB_TYPE || 'sqlite';
+}
+
+/**
+ * Generate a unique ID appropriate for the database type.
+ * - SQLite: returns nanoid (21-char alphanumeric)
+ * - PostgreSQL: returns UUID v4
+ */
 export function generateId(): string {
-  return nanoid(21);
+  return getDbType() === 'postgres' ? randomUUID() : nanoid(21);
 }
 
 export function generateTicketCode(): string {
   return `TKT-${nanoid(8).toUpperCase()}`;
 }
 
-export function getNow(): string {
-  return new Date().toISOString();
+/**
+ * Get current timestamp in the format appropriate for the database type.
+ * - SQLite: returns ISO string
+ * - PostgreSQL: returns Date object
+ */
+export function getNow(): string | Date {
+  const now = new Date();
+  return getDbType() === 'postgres' ? now : now.toISOString();
+}
+
+/**
+ * Convert a date value to the appropriate format for the database type.
+ * - SQLite: returns ISO string
+ * - PostgreSQL: returns Date object
+ */
+export function toDbDate(date: Date | string): string | Date {
+  const d = typeof date === 'string' ? new Date(date) : date;
+  return getDbType() === 'postgres' ? d : d.toISOString();
+}
+
+/**
+ * Convert a boolean value to the appropriate format for the database type.
+ * - SQLite: returns boolean (true/false) for mode: 'boolean'
+ * - PostgreSQL: returns integer (1/0) for pgInteger columns
+ */
+export function toDbBool(value: boolean): boolean | number {
+  return getDbType() === 'postgres' ? (value ? 1 : 0) : value;
+}
+
+/**
+ * Convert all boolean values in an object to the appropriate database format.
+ * Useful for converting request data before database insert/update.
+ */
+export function convertBooleansForDb<T extends Record<string, any>>(obj: T): T {
+  if (getDbType() !== 'postgres') {
+    return obj; // SQLite handles booleans automatically
+  }
+  
+  const result = { ...obj };
+  for (const key in result) {
+    if (typeof result[key] === 'boolean') {
+      (result as any)[key] = result[key] ? 1 : 0;
+    }
+  }
+  return result;
 }
 
 export function formatCurrency(amount: number, currency: string = 'PYG'): string {