Include real OS info in metrics. (#10425)

calculated a hashed user ID from either auth user id or API key
Also correctly populates OS.

These will make our metrics more useful and powerful for analysis.

codex-rs/otel/src/lib.rs

@@ -14,6 +14,7 @@ use crate::metrics::validation::validate_tag_key;
 use crate::metrics::validation::validate_tag_value;
 use crate::otel_provider::OtelProvider;
 use codex_protocol::ThreadId;
+pub use codex_utils_string::sanitize_metric_tag_value;
 use opentelemetry_sdk::metrics::data::ResourceMetrics;
 use serde::Serialize;
 use std::time::Duration;
@@ -188,7 +189,7 @@ impl OtelManager {
         if !self.metrics_use_metadata_tags {
             return Ok(Vec::new());
         }
-        let mut tags = Vec::with_capacity(6);
+        let mut tags = Vec::with_capacity(5);
         Self::push_metadata_tag(&mut tags, "auth_mode", self.metadata.auth_mode.as_deref())?;
         Self::push_metadata_tag(
             &mut tags,