Need help restoring the bootloader after an unsuccessful resizing attempt

I tried to solve a problem with ChatGPT without really understanding what I was doing. As a result, I filled up my 100MB bootloader partition, and it only has a single generation. Running sudo nix-collect-garbage -d didn’t remove anything, so I tried to resize the bootloader partition. I did resize it, but the filesystem still showed as 100MB instead of using the whole partition (5GB). So, in a similar manner, I tried to fix the problem by formatting the partition as ext4, extending the filesys...