Signature Customization

Signature styling and customization improvements:

• Add the ability to change logo images for Replies and Forwards (different from New Messages)

• Add the ability to adjust padding/space at the top of the signature

• Per-line typography control: change font color, bold, italicize, and font size for each individual line/field

• Static text fields — ability to add a field with globally-set static content (beyond repurposing Company Address)

• Team Signature Data improvements — per-field bold, color, and font size (e.g. company name bold and in brand color, user name slightly larger than body text)