Expanded descriptions for rail mounted mandible guard

[Termineitor244]

Summary

Bugfixes "Expands some descriptions to make more clear that some mandible guard are rail mounted."

Purpose of change

Fixes #60086 (I hope).

Describe the solution

Some simple text additions.

Describe alternatives you've considered

Testing

None.

Additional context

[Maleclypse]

I saw this and wanted to to add a rail mounted flashlight like https://www.amazon.com/Tactical-Flashlight-Mounted-Compatible-MICH2000/dp/B09CNMMYDQ/ref=asc_df_B09CNMMYDQ/?tag=hyprod-20&linkCode=df0&hvadid=532845793812&hvpos=&hvnetw=g&hvrand=13742622480565808309&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9013478&hvtargid=pla-1460923253252&psc=1 but I don't think I have it in me right now.

[Termineitor244]

I saw this and wanted to to add a rail mounted flashlight like https://www.amazon.com/Tactical-Flashlight-Mounted-Compatible-MICH2000/dp/B09CNMMYDQ/ref=asc_df_B09CNMMYDQ/?tag=hyprod-20&linkCode=df0&hvadid=532845793812&hvpos=&hvnetw=g&hvrand=13742622480565808309&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9013478&hvtargid=pla-1460923253252&psc=1 but I don't think I have it in me right now.

I think I saw one of those when I was making the original PR, but decided against because its function is already totally occupied by the strapped flashlight and just having a flashlight in your inventory... But I don't know, I could end up adding it when I revisit some values of the attachments.