`_submit_fal_request` (image) and `_submit_fal_video_request` (video plugin)
translated every managed-gateway 4xx into "This model may not yet be enabled
on the Nous Portal's FAL proxy — set FAL_KEY or pick a different model". For
HTTP 429 that remediation is wrong: the gateway body is RATE_LIMIT_EXCEEDED
with a retryAfter, the model is enabled, and agents reading the message
switched models or gave up. On one real install this fired 260 times in a
week (17% of image_generate calls).
Both surfaces now submit through one shared helper
(tools/fal_common.py::submit_managed_fal_with_rate_limit_retry): a 429 whose
Retry-After (header, else body error.retryAfter) fits a 30s cap is waited out
in interrupt-aware 0.5s slices and resubmitted once under a fresh
x-idempotency-key; a second 429, or an unknown/too-long Retry-After, raises
a ValueError that names the rate limit and tells the agent to retry later
rather than switch models. 429 can no longer reach the "may not yet be
enabled" text.