Errors after some failed installations

[ple1n]

Before this the script download failed and maybe got interrupted during executions (may be a cause of errors)

Anyway, I ran into this problem

➜  by_projects ls -lh /home/phy/.zkm-toolchain/
total 407M
drwxr-xr-x. 1 phy phy   10 Aug 16 11:14 bin
-rw-r--r--. 1 phy phy  125 Aug 16 11:49 env
drwxr-xr-x. 1 phy phy   60 Jul 17 01:21 rust-toolchain-x86-64-unknown-linux-gnu-20250717
-rw-r--r--. 1 phy phy 407M Aug 16 11:18 rust-toolchain-x86-64-unknown-linux-gnu-20250717.tar.xz
-rw-r--r--. 1 phy phy    9 Aug 16 11:14 rust-toolchain-x86-64-unknown-linux-gnu-No.tar.xz

Here is the directory.

I succeeded in installing with ~/.zkm-toolchain/bin/zkmup setup -v 20250717 but anyway this needs to be more robust