chore: add Discord community announcement email + thumbnail (#279)

Draft artifacts for the TryPost Discord community launch email
(https://trypost.it/discord) — not tied to a version release.

releases/discord-community/email.md

@@ -0,0 +1,29 @@
+---
+subject: "Join us on Discord — let's build this in the open"
+---
+
+# I opened a Discord for the TryPost community
+
+Hey, it's Paulo. 👋
+
+I built TryPost because I couldn't stay consistent posting. Being a developer, I gave it an MCP server, and made it open source: AGPL, self-hostable, no seat tax, no feature gates.
+
+So I opened a Discord too.
+
+## What you'll find there
+
+You'll find people running TryPost self-hosted, and people paying for cloud, in the same room. Talking, helping each other out, sharing what they've built and what's breaking. That feedback is basically how I decide what to build next.
+
+Come say hi 👋
+
+<div style="text-align:center; margin:32px 0;">
+  <a href="https://trypost.it/discord" style="display:inline-block; background-color:#8b5cf6; color:#ffffff; font-family:sans-serif; font-weight:700; font-size:16px; padding:14px 32px; border-radius:10px; border:2px solid #0a0a0a; text-decoration:none;">Join the Discord →</a>
+</div>
+
+Cheers,
+Paulo from TryPost.it
+
+---
+
+You're receiving this because you subscribed.
+[Unsubscribe]({{unsubscribe_url}})