feat(obs): unify metrics initialization and fix exporter move error (#851)

* feat(obs): unify metrics initialization and fix exporter move error

- Fix Rust E0382 (use after move) by removing duplicate MetricExporter consumption.
- Consolidate MeterProvider construction into single Recorder builder path.
- Remove redundant Recorder::builder(...).install_global() call.
- Ensure PeriodicReader setup is performed only once (HTTP + optional stdout).
- Set global meter provider and metrics recorder exactly once.
- Preserve existing behavior for stdout/file vs HTTP modes.
- Minor cleanup: consistent resource reuse and interval handling.

* update telemetry.rs

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

* fix

* fix

* fix

* fix: modify logger level from error to event

---------

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

crates/obs/src/system/mod.rs

@@ -12,7 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-use crate::{GlobalError, is_observability_enabled};
+use crate::{GlobalError, observability_metric_enabled};
 use opentelemetry::{global::meter, metrics::Meter};
 use sysinfo::Pid;
 
@@ -29,7 +29,7 @@ impl SystemObserver {
     /// This function will create a new `Collector` instance and start collecting metrics.
     /// It will run indefinitely until the process is terminated.
     pub async fn init_process_observer() -> Result<(), GlobalError> {
-        if is_observability_enabled() {
+        if observability_metric_enabled() {
             let meter = meter("system");
             let pid = sysinfo::get_current_pid().map_err(|e| GlobalError::PidError(e.to_string()))?;
             return SystemObserver::init_process_observer_for_pid(meter, pid).await;