Fixing a bug where the wall time was added to the on_llm_end function… (#133)

* Fixing a bug where the wall time was added to the on_llm_end function in observability but not on_llm_error

* Removing irrelevant comment

Author: mikegros

src/ursa/observability/timing.py

@@ -745,14 +745,15 @@ def on_llm_end(self, response, *, run_id, **kwargs):
             "metadata": metadata,
             "metrics": metrics,
             "t_start": wall_t0,
-            "t_end": wall_t1,  # <— add these
+            "t_end": wall_t1,
         })
 
     def on_llm_error(self, error, *, run_id, **kwargs):
-        name, t0, tags, metadata = self._starts.pop(
+        name, t0, tags, metadata, wall_t0 = self._starts.pop(
             run_id, ("llm:unknown", time.perf_counter(), [], {})
         )
         ms = (time.perf_counter() - t0) * 1000.0
+        wall_t1 = time.time()
         self.agg.add(name, ms, False)
         self.samples.append({
             "name": name,
@@ -761,6 +762,8 @@ def on_llm_error(self, error, *, run_id, **kwargs):
             "tags": tags,
             "metadata": metadata,
             "metrics": {"error": repr(error)},
+            "t_start": wall_t0,
+            "t_end": wall_t1,
         })