feat: improve video conference UI in EventModal

- Replace 'Meeting link generated' text with 'Join Visio conference' button
- Button opens video conference link in new tab when clicked
- Use contained variant styling to match Save button appearance
- Maintain copy and delete functionality for meeting links

src/components/Calendar/TempCalendarsInput.tsx

@@ -1,4 +1,4 @@
-import { useState, useRef, useMemo } from "react";
+import { useState, useRef } from "react";
 import { useAppDispatch, useAppSelector } from "../../app/hooks";
 import {
   getTempCalendarsListAsync,