How I "killed" the router.
For the purpose of the experiment, the luci-app-irqbalance package with dependencies via Luci was installed on firmware 24.10.0. After installing this package, the interface and the router itself began to "slow down" very much and after a while spontaneously rebooted. After rebooting, it booted in recovery mode. This router has a recovery image installed -
4. *(Optional -10Mb free space) Add recovery boot feature.*
From under it, the 24.10.0 image was flashed _blah-blah-ubootmod-squashfs-sysupgrade.itb
But after rebooting, the router still loads the recovery firmware.
Just in case, I updated the U-BOOT files from the SNAPSHOT branch, it also didn't lead to anything, it boots into recovery mode.
I'm ready to try the software recovery options suggested by specialists before trying to roll back to stock using a backup copy and if there is a fiasco here, flashing via UART.
I have some time that I'm ready to spend to check the proposed recovery options.