fix(qlik): batch SelectValues to avoid Engine abort + drop couv stock metric

Large supplier (4816 codes) triggered Qlik Engine "Request aborted"
(code 15): a single SelectValues over all codes forced the hypercube to
calculate too many rows at once. Now select in 1200-code batches and
accumulate, keeping each calc small. 1417 codes worked before, 4816 did
not - chunking scales to any supplier.

Also remove the "Couverture de stock" network column end-to-end (grid,
types, Qlik clients, cache, schema, db-init), shifting the marge measure
index from 6 to 5 and the hypercube width from 7 to 6.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

src/types/grid.ts

@@ -115,8 +115,6 @@ export interface ProductRow {
     nbMagasinsReseau?: number;
     /** CA moyen par magasin réseau (productivité normalisée présence) */
     caParMagasinReseau?: number;
-    /** Couverture de stock quantité réseau (rotation : bas = tourne vite) */
-    couvertureStockReseau?: number;
     /** Taux de marge réseau (ratio brut Qlik, ex 0.32 = 32%) */
     margePctReseau?: number;
     /** Taux de présence réseau = nbMagasinsReseau / 270 */