ESP32: Migrate to Arduino 3.x (pioarduino)

[vidplace7]

Switch all ESP32 builds to pioarduino/platform-espressif32.

https://docs.espressif.com/projects/arduino-esp32/en/latest/migration_guides/2.x_to_3.0.html

Switching to Arduino-ESP32 3.x will be necessary in order to properly support newer Espressif MCUs (esp32h2, esp32c5, esp32c6, esp32p4, etc)

DRAFT for now, see below.

TODO:

• NimBLE Transition
  • With ESP-IDF 5.5.x NimBLE has been integrated, Arduino-ESP32 exposes this nimble via the BLE API
  • Existing NimBLE code should be transitioned to the (similar but not identical) BLE API.
  • https://github.com/espressif/arduino-esp32/tree/3.3.5/libraries/BLE
  • https://docs.espressif.com/projects/arduino-esp32/en/latest/api/ble.html
• ADC API Changes
• CI Work
  • https://github.com/pioarduino/platform-espressif32/blob/main/.github/workflows/examples.yml
• (original) ESP32 4MB flash overruns
  • Excluded AUDIO Module
• ESP32c6 4MB flash overruns

Depends on:

• Remove syslog lib (replace?)
  • PlatformIO: Restructure networking_base for re-use #8964
• NimBLE
  • PIO: Fix ESP32 sub-variant inheritance #8983
  • Fix NimBLE 2 migration #9118
• libpax
  • NOTE: libpax relies on bluetooth vhci APIs which DO NOT EXIST on esp32c6, esp32h2, or newer (c5, p4, etc)
  • Fixed for ESP32/s2/s3/c3 in @mverch67 fork. PR upstream?

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This PR is a continuation of the work in #8952

Huge shoutout / credit to @mverch67 who's initial work this is based upon #7180 ❤️