feat: Space Booking System - MVP complet

Sistem web pentru rezervarea de birouri și săli de ședință
cu flux de aprobare administrativă.

Stack: FastAPI + Vue.js 3 + SQLite + TypeScript

Features implementate:
- Autentificare JWT + Self-registration cu email verification
- CRUD Spații, Utilizatori, Settings (Admin)
- Calendar interactiv (FullCalendar) cu drag-and-drop
- Creare rezervări cu validare (durată, program, overlap, max/zi)
- Rezervări recurente (săptămânal)
- Admin: aprobare/respingere/anulare cereri
- Admin: creare directă rezervări (bypass approval)
- Admin: editare orice rezervare
- User: editare/anulare rezervări proprii
- Notificări in-app (bell icon + dropdown)
- Notificări email (async SMTP cu BackgroundTasks)
- Jurnal acțiuni administrative (audit log)
- Rapoarte avansate (utilizare, top users, approval rate)
- Șabloane rezervări (booking templates)
- Atașamente fișiere (upload/download)
- Conflict warnings (verificare disponibilitate real-time)
- Integrare Google Calendar (OAuth2)
- Suport timezone (UTC storage + user preference)
- 225+ teste backend

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

frontend/src/utils/datetime.ts

@@ -0,0 +1,117 @@
+/**
+ * Utility functions for timezone-aware datetime formatting.
+ */
+
+/**
+ * Format a datetime string in the user's timezone.
+ *
+ * @param datetime - ISO datetime string from API (in UTC)
+ * @param timezone - IANA timezone string (e.g., "Europe/Bucharest")
+ * @param options - Intl.DateTimeFormat options
+ * @returns Formatted datetime string
+ */
+export const formatDateTime = (
+  datetime: string,
+  timezone: string = 'UTC',
+  options?: Intl.DateTimeFormatOptions
+): string => {
+  const date = new Date(datetime)
+
+  const defaultOptions: Intl.DateTimeFormatOptions = {
+    timeZone: timezone,
+    year: 'numeric',
+    month: '2-digit',
+    day: '2-digit',
+    hour: '2-digit',
+    minute: '2-digit',
+    ...options
+  }
+
+  return new Intl.DateTimeFormat('ro-RO', defaultOptions).format(date)
+}
+
+/**
+ * Format date only (no time) in user's timezone.
+ */
+export const formatDate = (datetime: string, timezone: string = 'UTC'): string => {
+  return formatDateTime(datetime, timezone, {
+    year: 'numeric',
+    month: '2-digit',
+    day: '2-digit',
+    hour: undefined,
+    minute: undefined
+  })
+}
+
+/**
+ * Format time only in user's timezone.
+ */
+export const formatTime = (datetime: string, timezone: string = 'UTC'): string => {
+  const date = new Date(datetime)
+  return new Intl.DateTimeFormat('ro-RO', {
+    timeZone: timezone,
+    hour: '2-digit',
+    minute: '2-digit'
+  }).format(date)
+}
+
+/**
+ * Format datetime with timezone abbreviation.
+ */
+export const formatDateTimeWithTZ = (datetime: string, timezone: string = 'UTC'): string => {
+  const date = new Date(datetime)
+
+  const formatted = new Intl.DateTimeFormat('ro-RO', {
+    timeZone: timezone,
+    year: 'numeric',
+    month: '2-digit',
+    day: '2-digit',
+    hour: '2-digit',
+    minute: '2-digit',
+    timeZoneName: 'short'
+  }).format(date)
+
+  return formatted
+}
+
+/**
+ * Get timezone abbreviation (e.g., "EET", "EEST").
+ */
+export const getTimezoneAbbr = (timezone: string = 'UTC'): string => {
+  const date = new Date()
+  const formatted = new Intl.DateTimeFormat('en-US', {
+    timeZone: timezone,
+    timeZoneName: 'short'
+  }).format(date)
+
+  // Extract timezone abbreviation from formatted string
+  const match = formatted.match(/,\s*(.+)/)
+  return match ? match[1] : timezone.split('/').pop() || 'UTC'
+}
+
+/**
+ * Convert local datetime-local input to ISO string (for API).
+ * The input from datetime-local is in user's local time, so we just add seconds and Z.
+ */
+export const localDateTimeToISO = (localDateTime: string): string => {
+  // datetime-local format: "YYYY-MM-DDTHH:mm"
+  // We need to send it as is to the API (API will handle timezone conversion)
+  return localDateTime + ':00'
+}
+
+/**
+ * Convert ISO datetime to datetime-local format for input field.
+ */
+export const isoToLocalDateTime = (isoDateTime: string, timezone: string = 'UTC'): string => {
+  const date = new Date(isoDateTime)
+
+  // Get the date components in the user's timezone
+  const year = date.toLocaleString('en-US', { timeZone: timezone, year: 'numeric' })
+  const month = date.toLocaleString('en-US', { timeZone: timezone, month: '2-digit' })
+  const day = date.toLocaleString('en-US', { timeZone: timezone, day: '2-digit' })
+  const hour = date.toLocaleString('en-US', { timeZone: timezone, hour: '2-digit', hour12: false })
+  const minute = date.toLocaleString('en-US', { timeZone: timezone, minute: '2-digit' })
+
+  // Format as YYYY-MM-DDTHH:mm for datetime-local input
+  return `${year}-${month}-${day}T${hour.padStart(2, '0')}:${minute}`
+}