feat: add video conference meeting link generation to event modal

- Add video conference utility functions for generating random meeting IDs
- Implement video meeting button with camera icon in EventModal
- Add copy and delete functionality with IconButton components
- Support X-OPENPAAS-VIDEOCONFERENCE field in CalendarEvent type
- Handle state management for editing events with/without video conference
- Add meeting link footer to event description
- Include comprehensive test suite for video conference utilities

Features:
- Generate random meeting links (format: xxx-xxxx-xxx)
- Copy meeting link to clipboard
- Remove video conference from events
- Proper state sync when editing different events
- Integration with existing JCal/ICS conversion

src/utils/__test__/videoConferenceUtils.test.ts

@@ -0,0 +1,65 @@
+import { generateMeetingId, generateMeetingLink, addVideoConferenceToDescription, extractVideoConferenceFromDescription } from '../videoConferenceUtils';
+
+describe('videoConferenceUtils', () => {
+  describe('generateMeetingId', () => {
+    it('should generate meeting ID in correct format', () => {
+      const meetingId = generateMeetingId();
+      expect(meetingId).toMatch(/^[a-z]{3}-[a-z]{4}-[a-z]{3}$/);
+    });
+
+    it('should generate different IDs each time', () => {
+      const id1 = generateMeetingId();
+      const id2 = generateMeetingId();
+      expect(id1).not.toBe(id2);
+    });
+  });
+
+  describe('generateMeetingLink', () => {
+    it('should generate link with default base URL', () => {
+      const link = generateMeetingLink();
+      expect(link).toMatch(/^https:\/\/meet\.linagora\.com\/[a-z]{3}-[a-z]{4}-[a-z]{3}$/);
+    });
+
+    it('should generate link with custom base URL', () => {
+      const customBase = 'https://custom-meet.example.com';
+      const link = generateMeetingLink(customBase);
+      expect(link).toMatch(/^https:\/\/custom-meet\.example\.com\/[a-z]{3}-[a-z]{4}-[a-z]{3}$/);
+    });
+  });
+
+  describe('addVideoConferenceToDescription', () => {
+    it('should add video conference footer to empty description', () => {
+      const description = '';
+      const meetingLink = 'https://meet.linagora.com/abc-defg-hij';
+      const result = addVideoConferenceToDescription(description, meetingLink);
+      expect(result).toBe('\n\nVisio: https://meet.linagora.com/abc-defg-hij');
+    });
+
+    it('should add video conference footer to existing description', () => {
+      const description = 'This is a meeting description.';
+      const meetingLink = 'https://meet.linagora.com/abc-defg-hij';
+      const result = addVideoConferenceToDescription(description, meetingLink);
+      expect(result).toBe('This is a meeting description.\n\nVisio: https://meet.linagora.com/abc-defg-hij');
+    });
+  });
+
+  describe('extractVideoConferenceFromDescription', () => {
+    it('should extract video conference link from description', () => {
+      const description = 'Meeting description.\n\nVisio: https://meet.linagora.com/abc-defg-hij';
+      const result = extractVideoConferenceFromDescription(description);
+      expect(result).toBe('https://meet.linagora.com/abc-defg-hij');
+    });
+
+    it('should return null when no video conference link found', () => {
+      const description = 'Just a regular meeting description.';
+      const result = extractVideoConferenceFromDescription(description);
+      expect(result).toBeNull();
+    });
+
+    it('should return null for empty description', () => {
+      const description = '';
+      const result = extractVideoConferenceFromDescription(description);
+      expect(result).toBeNull();
+    });
+  });
+});

src/utils/videoConferenceUtils.ts

@@ -0,0 +1,48 @@
+/**
+ * Utility functions for video conference meeting generation
+ */
+
+/**
+ * Generate a random meeting ID in format xxx-xxxx-xxx
+ * @returns {string} Random meeting ID
+ */
+export function generateMeetingId(): string {
+  const chars = 'abcdefghijklmnopqrstuvwxyz';
+  const generateSegment = (length: number): string => {
+    return Array.from({ length }, () => chars[Math.floor(Math.random() * chars.length)]).join('');
+  };
+  
+  return `${generateSegment(3)}-${generateSegment(4)}-${generateSegment(3)}`;
+}
+
+/**
+ * Generate a complete meeting link
+ * @param {string} baseUrl - Base URL for video conference (from .env.js)
+ * @returns {string} Complete meeting link
+ */
+export function generateMeetingLink(baseUrl?: string): string {
+  const base = baseUrl || (window as any).VIDEO_CONFERENCE_BASE_URL || 'https://meet.linagora.com';
+  const meetingId = generateMeetingId();
+  return `${base}/${meetingId}`;
+}
+
+/**
+ * Add video conference footer to event description
+ * @param {string} description - Original description
+ * @param {string} meetingLink - Generated meeting link
+ * @returns {string} Description with video conference footer
+ */
+export function addVideoConferenceToDescription(description: string, meetingLink: string): string {
+  const footer = `\n\nVisio: ${meetingLink}`;
+  return description + footer;
+}
+
+/**
+ * Extract video conference link from description
+ * @param {string} description - Event description
+ * @returns {string | null} Video conference link if found, null otherwise
+ */
+export function extractVideoConferenceFromDescription(description: string): string | null {
+  const match = description.match(/Visio:\s*(https?:\/\/[^\s]+)/);
+  return match ? match[1] : null;
+}