refactor: Phase 1 code consolidation and service layer setup

Phase 1.1: Shared parsers utility
- Create backend/src/utils/parsers.js with parseBooleanInput, parseStringInput, etc.
- Create frontend/src/utils/parsers.ts with TypeScript equivalents
- Update routes to import from shared parsers

Phase 1.2: Auth routes consolidation
- Merge auth.js, auth-enhanced.js, auth-enhanced-v2.js into single auth.js
- Add password change and password strength endpoints
- Consolidate middleware (auth.js with token revocation support)
- Update all imports across 14+ route files

Phase 1.3: CreateEvent page consolidation
- Remove duplicate CreateEventPage.tsx (basic version)
- Rename CreateEventPageEnhanced.tsx to CreateEventPage.tsx
- Update exports and imports

Phase 1.4: CMS page consolidation
- Remove duplicate CMSPage.tsx (basic version)
- Rename CMSPageEnhanced.tsx to CMSPage.tsx
- Update exports and imports

Phase 1.5: Multer config factory
- Create backend/src/config/multerConfig.js
- Centralized upload configuration with presets for photos, logos, favicons
- Reusable helpers: createDiskStorage, createFileFilter, uploadTimeoutMiddleware

Phase 2.1: Event service layer
- Create backend/src/services/eventService.js
- Move event business logic out of routes
- Functions: createEvent, getAllEvents, updateEvent, deleteEvent, extendExpiration

frontend/src/utils/parsers.ts

@@ -0,0 +1,166 @@
+/**
+ * Shared Parser Utilities for Frontend
+ * Pure functions for parsing and transforming input values
+ *
+ * @module utils/parsers
+ */
+
+/**
+ * Parse any input value to boolean with configurable default
+ * Handles: boolean, number, string representations
+ *
+ * @param value - Input value to parse
+ * @param defaultValue - Default if value is undefined/null
+ * @returns boolean result
+ *
+ * @example
+ * toBoolean(true) // true
+ * toBoolean('false') // false
+ * toBoolean('1') // true
+ * toBoolean(0) // false
+ * toBoolean(undefined, false) // false
+ */
+export const toBoolean = (value: unknown, defaultValue = false): boolean => {
+  if (value === undefined || value === null) {
+    return defaultValue;
+  }
+  if (typeof value === 'boolean') {
+    return value;
+  }
+  if (typeof value === 'number') {
+    if (Number.isNaN(value)) return defaultValue;
+    return value !== 0;
+  }
+  if (typeof value === 'string') {
+    const normalized = value.toLowerCase().trim();
+    if (['true', '1', 'yes', 'on'].includes(normalized)) return true;
+    if (['false', '0', 'no', 'off', ''].includes(normalized)) return false;
+  }
+  return defaultValue;
+};
+
+/**
+ * Parse numeric input with validation and optional bounds
+ *
+ * @param value - Input value to parse
+ * @param defaultValue - Default if invalid
+ * @param options - Bounds options
+ * @returns number result
+ *
+ * @example
+ * toNumber('42', 0) // 42
+ * toNumber('abc', 10) // 10
+ * toNumber(5, 0, { min: 10 }) // 10
+ */
+export const toNumber = (
+  value: unknown,
+  defaultValue: number,
+  options?: { min?: number; max?: number }
+): number => {
+  if (value === undefined || value === null || value === '') {
+    return defaultValue;
+  }
+
+  const parsed = Number(value);
+  if (!Number.isFinite(parsed)) {
+    return defaultValue;
+  }
+
+  let result = parsed;
+  if (options?.min !== undefined && result < options.min) result = options.min;
+  if (options?.max !== undefined && result > options.max) result = options.max;
+
+  return result;
+};
+
+/**
+ * Parse string input with trimming and null handling
+ *
+ * @param value - Input value
+ * @param defaultValue - Default if empty
+ * @returns string or null
+ *
+ * @example
+ * toString('  hello  ') // 'hello'
+ * toString('') // null
+ * toString(null, 'default') // 'default'
+ */
+export const toString = (value: unknown, defaultValue: string | null = null): string | null => {
+  if (value === undefined || value === null) {
+    return defaultValue;
+  }
+  if (typeof value === 'string') {
+    const trimmed = value.trim();
+    return trimmed || defaultValue;
+  }
+  return String(value);
+};
+
+/**
+ * Parse JSON string safely
+ *
+ * @param value - JSON string or already parsed value
+ * @param defaultValue - Default if parsing fails
+ * @returns parsed value or default
+ */
+export const parseJson = <T>(value: unknown, defaultValue: T): T => {
+  if (value === undefined || value === null) {
+    return defaultValue;
+  }
+  if (typeof value !== 'string') {
+    return value as T;
+  }
+  try {
+    return JSON.parse(value) as T;
+  } catch {
+    return defaultValue;
+  }
+};
+
+/**
+ * Parse date input to Date object
+ *
+ * @param value - Date string, Date object, or timestamp
+ * @returns Date object or null if invalid
+ */
+export const toDate = (value: unknown): Date | null => {
+  if (value === undefined || value === null || value === '') {
+    return null;
+  }
+  if (value instanceof Date) {
+    return isNaN(value.getTime()) ? null : value;
+  }
+  const date = new Date(value as string | number);
+  return isNaN(date.getTime()) ? null : date;
+};
+
+/**
+ * Parse array input (handles JSON strings and arrays)
+ *
+ * @param value - Array or JSON string
+ * @param defaultValue - Default if invalid
+ * @returns array result
+ */
+export const toArray = <T>(value: unknown, defaultValue: T[] = []): T[] => {
+  if (value === undefined || value === null) {
+    return defaultValue;
+  }
+  if (Array.isArray(value)) {
+    return value as T[];
+  }
+  if (typeof value === 'string') {
+    try {
+      const parsed = JSON.parse(value);
+      return Array.isArray(parsed) ? parsed : defaultValue;
+    } catch {
+      // Try comma-separated for string arrays
+      return value.split(',').map(s => s.trim()).filter(Boolean) as T[];
+    }
+  }
+  return defaultValue;
+};
+
+// Re-export with alternative names for backwards compatibility
+export const parseBooleanInput = toBoolean;
+export const parseNumberInput = toNumber;
+export const parseStringInput = toString;