fix(tools): say when get_wind answers from a stale forecast run

When the model upstream fails, the wind proxy keeps serving its last
run, however old, with manifest.stale set. The wind layer shows that,
but get_wind ignored it and gave the old run's wind as current.

get_wind now returns stale and adds "(forecast may be stale)" to its
summary, the way get_weather and the space tools flag stale data.

Co-Authored-By: Claude Opus 5.5 <[email protected]>

docs/CURRENT-STATE.md

@@ -5827,7 +5827,7 @@ closed. Performance and live agency reliability require recorded validation.
 
 ## Wind forecast models
 
-Wind supports selectable GFS/IFS models with persisted model choice. Each fetch chooses the available cycle and forecast step nearest the current time; rows show both issue and valid UTC timestamps. Grid identities include model, cycle, forecast step and any requested scalar field. The six model/field cache slots each retain the last two issued grids for manifest/grid rollover, coalesce concurrent requests, retain last-good data on failures and retry no faster than once per minute. Model changes clear the old field immediately, cancel old acquisition and ignore superseded results.
+Wind supports selectable GFS/IFS models with persisted model choice. Each fetch chooses the available cycle and forecast step nearest the current time; rows show both issue and valid UTC timestamps. Grid identities include model, cycle, forecast step and any requested scalar field. The six model/field cache slots each retain the last two issued grids for manifest/grid rollover, coalesce concurrent requests, retain last-good data on failures and retry no faster than once per minute. Model changes clear the old field immediately, cancel old acquisition and ignore superseded results. Last-good data is marked stale; the wind row shows it, and `get_wind` returns `stale` and adds "(forecast may be stale)" to its summary.
 
 ### Local Weather review candidate