bug: target_qps hardcoded to 10.0 in Offline mode instead of None

Problem

In src/inference_endpoint/config/runtime_settings.py:142-148, target_qps falls back to a hardcoded 10.0 for Offline (max_throughput) mode instead of None:

# TODO: target_qps should be None in Offline mode but using 10.0 as fallback
# to avoid breaking changes
target_qps = config.settings.target_qps or 10.0

In Offline/max_throughput mode, target_qps is semantically irrelevant — all queries are issued at t=0 as a burst. Having it default to 10.0 is misleading and can affect any downstream logic that reads this field.

Expected Behavior

target_qps should be None when the load pattern is max_throughput. The fallback workaround should be removed and callers that depend on this field should be updated to handle None.

Files to Modify

• src/inference_endpoint/config/runtime_settings.py
• Any callers that read runtime_settings.target_qps without a None check

Start in src/inference_endpoint/config/runtime_settings.py:142-148 and trace how target_qps is assigned for max_throughput. Search for callers that read runtime_settings.target_qps, then update handling so Offline mode preserves None without breaking other load patterns. Done means target_qps is None for max_throughput and all affected callers handle it safely.