feat(summarization): Route s4s traffic to new pod (#97926)

## PR details
+ Routing issue summary s4s traffic to new summarization pod

Author: Mihir-Mavalankar

src/sentry/options/defaults.py

@@ -949,6 +949,14 @@
     flags=FLAG_AUTOMATOR_MODIFIABLE,
 )
 
+# Rollout rate to route issue summary requests to the summarization URL
+register(
+    "issues.summary.summarization-url-rollout-rate",
+    type=Float,
+    default=0.0,
+    flags=FLAG_AUTOMATOR_MODIFIABLE,
+)
+
 register(
     "issues.priority.projects-allowlist",
     type=Sequence,

src/sentry/seer/autofix/issue_summary.py

@@ -161,8 +161,13 @@ def _call_seer(
         option=orjson.OPT_NON_STR_KEYS,
     )
 
+    url = settings.SEER_AUTOFIX_URL
+    # Route to summarization URL based on rollout rate
+    if in_random_rollout("issues.summary.summarization-url-rollout-rate"):
+        url = settings.SEER_SUMMARIZATION_URL
+
     response = requests.post(
-        f"{settings.SEER_AUTOFIX_URL}{path}",
+        f"{url}{path}",
         data=body,
         headers={
             "content-type": "application/json;charset=utf-8",