Images in email newsletters don’t preempt auto dark mode

[dnywh]

Some iOS email clients (Gmail, Outlook) do their own bespoke forced dark mode styling on email contents. I’ve preempted this on the Peels logo but any imagery is dulled. See the below table.

Ideally these either override the dark mode or have a white background fill to reduce the dulling.

Gmail on iOS	Outlook on iOS

Affected component: NewsletterIssueOneEmail, handled via Supabase edge functions (and therefore in the supabase root directory).