Enable usage of PSRAM

[iranl]

Description:

Add support for using PSRAM if the device has PSRAM.
Does nothing if no PSRAM is available.

ESP32-S3 gets a separate build for devices with Octal SPI PSRAM.
Regular build will work with Quad SPI PSRAM.
Both will work with devices without PSRAM.

Also add a section to the README with recommended variants based on use case and section about memory constraints.

Part of info page on a ESP32-S3 N16R8 with MQTT SSL enabled and pretty high Nuki/Network task sizes set showing >8MB of free Heap:

------------ NUKI HUB ------------
Version: 9.01
Build: unknownbuildnr
Build type: Release
Build date: 2024-08-23
Updater version: 9.01-master12
Updater build: 10490297298.49.1
Updater build date: 2024-08-18
Uptime (min): 332
Config version: 901
Last restart reason FW: RebootToOTA
Last restart reason ESP: ESP_RST_SW: Software reset via esp_restart.
Free internal heap: 115623
Total internal heap: 370835
PSRAM Available: Yes
Total PSRAM: 8388608
Free PSRAM: 8315489
Total free heap: 8431112
Network task stack high watermark: 16756
Nuki task stack high watermark: 8920

------------ GENERAL SETTINGS ------------
Network task stack size: 22528
Nuki task stack size: 12288

Checklist:

• The pull request is done against the latest master branch
• Only relevant files were touched
• Only one feature/fix was added per PR and the code change compiles without warnings
• The code change is tested and works
• I accept the CLA.