Keep the upstream project's name out of user-visible strings

The first-party application descriptions and the telemetry service name and
instrumentation scope are shown to operators, and the unpacked-application
temp directory carried the name too.

Left alone deliberately: the OAuth key-derivation contexts (renaming them
would invalidate every sealed token and client id), the migration defaults
that read an upstream installation, links to upstream's upgrade guide, the
wire-protocol identifiers, and upstream's own license and templates.

crates/common/src/telemetry/tracers/otel.rs

@@ -29,11 +29,11 @@ pub(crate) fn spawn_otel_tracer(builder: SubscriberBuilder, mut otel: OtelTracer
     let (_, mut rx) = builder.register();
     tokio::spawn(async move {
         let resource = Resource::builder()
-            .with_service_name("stalwart")
+            .with_service_name("inbuxa")
             .with_attribute(KeyValue::new(SERVICE_VERSION, types::brand_version_full!()))
             .build();
 
-        let instrumentation = InstrumentationScope::builder("stalwart")
+        let instrumentation = InstrumentationScope::builder("inbuxa")
             .with_version(types::brand_version_full!())
             .build();