Completion support for SLURM workload manger

[saiden89]

Hi everyone, I've been working (mostly for myself) on adding command completions for SLURM, a popular workload manager used on HPC clusters and supercomputers. SLURM has a comprehensive set of commands and options, and having completions available in Fish Shell significantly improves usability for users managing jobs and resources on HPC systems, especially novices.

This has been a long and tedious process due to the complexity of SLURM's commands and the intricate logic required for some arguments. For example, certain options depend on cluster-specific configurations or need dynamic handling based on the state of the system.

Some of the completions are already functional, but implementing the more complicated ones—particularly those involving dynamic logic, cluster-specific options, or system state dependencies—has proven challenging.

I am curious if this is something the community would find useful. While SLURM is commonly used in HPC environments, it may be considered niche.