fix(odin): add -stdin flag to odinfmt

[ATTron]

fix(lang/odin): pass -stdin to odinfmt

The current bare invocation of the odin lang formatter '("odinfmt")' fails and exits 1, so format-on-save never applies due to the buffer being passed through stdin and odinfmt not be able to read it.

Add the -stdin flag to match odinfmt's documented setup and resolve the exit 1 from odinfmt

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