New

• tracking: add vanity tracking domain support (em.customer-domain)
• newsletter microapp with signup forms, double opt-in, and blog integration #288

Fixed

• worker: use Recreate strategy for hostNetwork deployment #296
• landing: improve hero copy, feature links, text contrast, and registration UX #295
• dns: update SPF record with correct SMTP node IPs and IPv6
• landing: use url-encoded form body for newsletter signup
• tests: register sidebar nav template in GDPR dashboard tests
• suppress clippy too_many_arguments for query and task functions
• apply cargo fmt formatting to newsletter microapp code