mobile sticker width + text baseline + theme colors

[ygg2]

Description

• on mobile, sticker will not exceed message width (height: auto is to preserve aspect ratio)
• adjusted vertical alignment of user info and reply text to visual baseline (icons centered)

Edits

• added unrelated fix for non-square pfps to not get stretched
• also matched the style of DMs to the existing channel styles so it works with all themes/matches expectations
• also adjusted colors on the gif picker to work with all themes/match sticker and emoji popups