fix(harfanglab): retry transient API errors (1.7.3)

HarfangLab answers a 500 now and then on a call that passes when sent
again. Each script's request() now retries up to three times (1, 2, 4 s):
GET on 429/500/502/503/504, writes only on 429/502/503 so an isolation,
a kill or a job is never sent twice.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

integrations/harfanglab/scripts/wait_for_job.py

@@ -1,12 +1,31 @@
 import json, os, sys, time, urllib.request, urllib.parse, urllib.error
 
 
+RETRIES = 3
+
+
+def retryable(method, status):
+    # HarfangLab answers a 500 now and then on a call that passes when sent again.
+    # A read is safe to resend; a write only on an answer that says the action was
+    # not run (rate limit, gateway down), so an isolation or a job is never sent twice.
+    if status in (429, 502, 503):
+        return True
+    return method == "GET" and status in (500, 504)
+
+
 def request(method, url, headers, body=None):
     data = json.dumps(body).encode("utf-8") if body is not None else None
-    req = urllib.request.Request(url, data=data, headers=headers, method=method)
-    with urllib.request.urlopen(req, timeout=60) as resp:
-        raw = resp.read()
-        return json.loads(raw) if raw else {}
+    for attempt in range(RETRIES + 1):
+        req = urllib.request.Request(url, data=data, headers=headers, method=method)
+        try:
+            with urllib.request.urlopen(req, timeout=60) as resp:
+                raw = resp.read()
+                return json.loads(raw) if raw else {}
+        except urllib.error.HTTPError as e:
+            if attempt == RETRIES or not retryable(method, e.code):
+                raise
+            e.close()
+            time.sleep(2 ** attempt)
 
 
 def main():