886ce1b87c
ISqlDialect gains MaxBindParameters — the per-command ceiling the seam was missing while modelling everything else that differs per backend: 2098 usable of SQL Server's 2100 (sp_executesql spends two), 1000 for Oracle's IN-list limit (ORA-01795, tighter than its 64k bind count), 65535 for the Postgres Bind message. SqlGroupPlanner.AddKeyValuePlans now emits several plans for one group when its distinct keys exceed that ceiling, instead of one statement the provider refuses after the connection opened — which left every tag in an EAV group publishing BadCommunicationError on every poll, permanently, and reported the database endpoint as down. Chunks share the group key; members follow their own key so a shared keyValue never splits. SqlPollReader is unchanged: it runs one command per plan and slices each plan's own Members back, proven by a fixture read at a ceiling of 1.