Rebrand to INBUXA: product name, protocol greetings, sign-in page, calendar templates, logos, README

One branding module (types::brand!) supplies the name to every protocol
greeting, the HTTP realm, the startup banner, Received headers, the
user agent, the IMAP ID response and calendar PRODIDs. The sign-in and
calendar pages take ihasmail's palette and font and the INBUXA logo, and
calendar emails embed the INBUXA lockup. Default calendar and address book
names follow. Protocol identifiers (urn:stalwart:jmap, vnd.stalwart Sieve
extensions) and upstream copyright notices are unchanged.

crates/trc/src/event/enums_impl.rs

@@ -3661,8 +3661,8 @@ impl EventType {
             EventType::Security(SecurityEvent::IpAllowExpired) => "IP allow expired",
             EventType::Security(SecurityEvent::IpUnauthorized) => "Unauthorized IP address",
             EventType::Security(SecurityEvent::Unauthorized) => "Unauthorized access",
-            EventType::Server(ServerEvent::Startup) => "Starting Stalwart Server",
-            EventType::Server(ServerEvent::Shutdown) => "Shutting down Stalwart Server",
+            EventType::Server(ServerEvent::Startup) => "Starting INBUXA Server",
+            EventType::Server(ServerEvent::Shutdown) => "Shutting down INBUXA Server",
             EventType::Server(ServerEvent::StartupError) => "Server startup error",
             EventType::Server(ServerEvent::ThreadError) => "Server thread error",
             EventType::Server(ServerEvent::Licensing) => "Server licensing event",