arg: fix order to use short form before long form

[ServeurpersoCom]

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Minor cosmetics for logs :
Fixes argument order to follow convention: short form before long form (e.g., {"-x", "--xxx"} instead of {"--xxx", "-x"}).

This affects how arguments appear in logs since to_string() uses .back().

Found via: grep -n '{"--[a-z-]*", "-[a-z]' common/arg.cpp

Fixed 8 arguments:

• -cram, --cache-ram
• -kvu, --kv-unified
• -ot, --override-tensor
• -otd, --override-tensor-draft
• -cmoe, --cpu-moe
• -ncmoe, --n-cpu-moe
• -cmoed, --cpu-moe-draft
• -ncmoed, --n-cpu-moe-draft

[ngxson]

I think it's worth adding a check in test-arg-parser too:

• If the option has more than one argument, make sure the first argument is shorter than the second
• Apply the same check with arg_neg

[ServeurpersoCom]

"the SRV_INF macro should already be prefixed with the function name, so I think this is not necessary:
#define SRV_INF(fmt, ...) LOG_INF("srv %12.*s: " fmt, 12, func, VA_ARGS)"
Nice!

This PR just need test-arg-parser order with arg_neg