Change sechailer flags + cleanup a bit of gasmask code

[kyunkyunkyun]

What Does This PR Do

Moves all security swat masks under sechailer/swat.
Removes HIDEEARS flag from sechailer, allowing you to see headsets you are wearing. Swat sechailer is not touched.
Moves bane mask under mask/gas.
Changes tajaran sechailer icon a bit, so it's not hiding your hud's brightest pixel (just look how it is on images).
Gives bane and blue swat masks an actually existing item state of sechailer.
Removes repeated flags, they share them from their parent anyways.

Why It's Good For The Game

It looks better, i believe.

Images of changes

Before the changes:

After the changes:

Tajaran before the changes (looks like a mask is on his eyes literally):

After:

Testing

On local. It works as intended.

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Declaration

• I confirm that I either do not require pre-approval for this PR, or I have obtained such approval and have included a screenshot to demonstrate this below.

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Changelog

🆑
tweak: Security gas mask won't hide your headsets anymore.
imageadd: Tajaran security gas mask was changed a bit on the sides, allowing you to see wearable hud sunglasses.
/:cl: