* CI: retry transient HTTP timeouts in Studio smoke probes
The post() helper in the Studio inference smoke workflows does a single
urlopen with a 240s timeout against the local Studio server. On shared
runners this sporadically hits TimeoutError while the server is stalled,
failing the whole job for a transport hiccup; the same flake has recurred
across unrelated PRs on Linux and Windows (JSON/images and tool-calling
jobs) and passes on rerun.
Retry the probe up to 3 times on transport-level failures only
(TimeoutError, ConnectionError, non-HTTP URLError), 15s apart. HTTP
status errors still surface immediately, so genuine server failures are
unaffected. post_sse() is left unchanged: it has a 600s budget and has
not flaked.
* CI: retry only short probes so worst case fits the job budget
Some json-images calls pass timeout=600; three attempts there could spend
30 minutes in one step and hit the job's timeout-minutes instead of failing
with the Python error. Retry (3 attempts) only when timeout <= 300s, which
covers the observed flaky 180-240s probes; longer probes keep the pre-PR
single attempt.
* CI: give long smoke probes one capped retry
Round two of bounding the retries: timeout>300s probes previously got a
single attempt, so a transient stall in the 600s JSON-mode probes still
failed on first occurrence. Give them one retry with the attempt timeout
capped at 300s. Worst cases stay inside timeout-minutes: 240s probes
12.5 min, one 600s probe 15.25 min, the Windows JSON job's two long
probes 30.5 min against its 35 minute budget.