The ``grok-4.3`` (1M context) catalog entry was added on 2026-05-15
(ce0e189d3). Between 2026-04-10 (when ``grok-4`` at 256,000 was first
added by b57769718) and 2026-05-15, grok-4.3 slugs resolved via the
generic ``grok-4`` substring catch-all and that 256,000 value was
persisted to context_length_cache.yaml. Users who first queried
grok-4.3 in that 35-day window are stuck at 256K forever — the cache
is read at step 1 before the hardcoded defaults in step 8, so the
correct 1M entry is never reached.
Mirror the existing Kimi/Codex/MiniMax-M3 stale-cache guards: add
_model_name_suggests_grok_4_3() and an elif branch that drops any
cached value ≤ 256,000 for a grok-4.3 slug so the next lookup falls
through to the 1M hardcoded default.
Adds 4 regression tests: helper unit test, stale-drop-and-re-resolve,
correct-cache-preserved, and no-clobber for plain grok-4 (256K correct).
9756dff5fd