Schedule Update for Q3 and Q4 2026

[rftafas]

We had major changes in schedule.

• About v4.0:
  • new release date: NOV/26: https://github.com/espressif/arduino-esp32/wiki/Release-Roadmap-and-Management
  • based in ESP-IDF 6.1 or later.
  • it will have a second alfa, without a specific schedule, aiming on supporting ESP32-S31
  • Migration to 4.0.alfa should be taken with careful consideration.
• About v4.1
  • Postponed to 2027.
  • IDF Release is undefined.
• v3.3.x will continue to be supported.