AnimatedPixelClock v2.5.3

This is the first release from my fork. It follows upstream v2.3.1, and it is built for one board only: the Waveshare ESP32-S3-RGB-Matrix (32 MB flash, 16 MB PSRAM) driving a 128x64 HUB75 panel. That is the board I have flashed from the web flasher and watched boot, so it is the only one I am offering.

The fix that made me cut this release: opening the web portal could take the panel off the network. The panel kept running and the clock stayed on the screen, but it stopped answering until it was reset. I traced it over USB. The Wi-Fi driver allocates its 1,626 byte receive buffers from the DMA-capable part of internal RAM, and one visit to the portal fired 48 requests, many of them at the same time. Every request waiting its turn held some of those buffers, the largest free DMA block fell from 11,252 to 1,396 bytes, and the radio could not get a buffer. The portal's own memory check was reading the wrong pool, which still showed 7,668 bytes free. In 2.5.3 the portal sends its requests one at a time, the memory check also looks at the DMA pool, and the link watchdog restarts Wi-Fi when it cannot even send a probe twice in a row, instead of waiting fifteen minutes. With all of that in place I clicked through every page, saved settings six times, reloaded the page and had two browsers open at once: 109 pings out of 109 answered and the radio did not fail a single allocation.

Since upstream v2.3.1 the panel has also gained:
Lua effects uploaded over the air, twelve slots of up to 50 KB each, so a new screen no longer needs a firmware flash.
Its own web flasher at https://nickoscope.github.io/AnimatedPixelClock/ with Wi-Fi setup in the browser.
A shared network broker, so the weather, flight board, rail board and other network screens take turns instead of each starting its own task.
A flight board fed directly from FlightAware AeroAPI, a Realtime Trains rail board, a world clock with your own cities, a yacht radar from AIS, a media player screen and a market screen, the last two through Home Assistant.
A presence radar screen that draws real targets from an mmWave sensor over MQTT.
No MQTT broker is assumed any more: the panel only connects to one after you give it an address.

Install: for a new board, use the web flasher above or write firmware-v2.5.3-waveshare.bin at 0x0. For a board that is already running, upload OTA_ONLY_firmware-v2.5.3-waveshare.bin on the portal's firmware update page, and do not upload the full image as an update. The Windows PC stats companion is pc_stats_monitor_v4.exe. SHA256SUMS.txt has the checksums.