trim conversation if it exceed max limit of what router model can handle (#488)

crates/brightstaff/src/utils/mod.rs

@@ -0,0 +1 @@
+pub mod tracing;

crates/brightstaff/src/utils/tracing.rs

@@ -0,0 +1,29 @@
+use std::sync::OnceLock;
+
+use opentelemetry::global;
+use opentelemetry_sdk::{propagation::TraceContextPropagator, trace::SdkTracerProvider};
+use opentelemetry_stdout::SpanExporter;
+use tracing_subscriber::EnvFilter;
+
+static INIT_LOGGER: OnceLock<SdkTracerProvider> = OnceLock::new();
+
+pub fn init_tracer() -> &'static SdkTracerProvider {
+    INIT_LOGGER.get_or_init(|| {
+        global::set_text_map_propagator(TraceContextPropagator::new());
+        // Install stdout exporter pipeline to be able to retrieve the collected spans.
+        // For the demonstration, use `Sampler::AlwaysOn` sampler to sample all traces.
+        let provider = SdkTracerProvider::builder()
+            .with_simple_exporter(SpanExporter::default())
+            .build();
+
+        global::set_tracer_provider(provider.clone());
+
+        tracing_subscriber::fmt()
+            .with_env_filter(
+                EnvFilter::try_from_default_env().unwrap_or_else(|_| EnvFilter::new("info")),
+            )
+            .init();
+
+        provider
+    })
+}