color_matrix_saturation() applies a bright red layer to everything when used in the oversaturation client colour.

Description of issue

/datum/client_color/oversaturated (applied when the druggy status is on a human mob) causes the game to become dark red. When color_matrix_saturation() is replaced with the previous colour saturation logic, the issue does not occur.

Difference between expected and actual behavior

Should be 1:1 with the legacy color saturation proc.

Steps to reproduce

Take a euphoriant drug.

Length of time in which bug has been known to occur

Likely since https://github.com/NebulaSS13/Nebula/pull/2903

Client version, Server revision & Game ID

Current staging branch.

Issue bingo

• Issue could be reproduced at least once
• Issue could be reproduced by different players
• Issue could be reproduced in multiple rounds
• Issue happened in a recent (less than 7 days ago) round
• Couldn't find an existing issue about this

Start with /datum/client_color/oversaturated and the color_matrix_saturation() call, then compare them with the previous colour saturation logic and the changes in PR 2903. Reproduce the issue by taking a euphoriant drug and verify that the oversaturated effect matches the legacy saturation behaviour without making the game dark red.