revert: restore grid to pre-infinite-scroll state

Remove infinite grid loading, useInfiniteGrid hook, and server-side
pagination API route. Revert grid components to the simpler version
that avoids 2MB+ cache failures from unstable_cache.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/features/grid/store/use-grid-store.ts

@@ -7,8 +7,6 @@ import type { GammeCode, GridFilters, GridSummary, ProductRow } from "@/types/gr
 interface GridState {
     /** Source data from server */
     rows: ProductRow[];
-    /** Index O(1) pour les lookups par codein (Map<codein, ProductRow>) */
-    rowsIndex: Map<string, ProductRow>;
     /** Draft edits: codein → new GammeCode */
     draftChanges: Record<string, GammeCode>;
     filters: GridFilters;
@@ -27,7 +25,6 @@ interface GridState {
 
     // Actions
     setRows: (rows: ProductRow[]) => void;
-    appendRows: (newRows: ProductRow[]) => void;
     setDraftGamme: (codein: string, gamme: GammeCode) => void;
     resetDrafts: () => void;
     /** Clear specific draft changes by codein */
@@ -67,7 +64,6 @@ export const useGridStore = create<GridState>()(
     persist(
         (set, get) => ({
             rows: [],
-            rowsIndex: new Map(),
             activeMagasin: "TOTAL",
             draftChanges: {},
             filters: {
@@ -98,27 +94,12 @@ export const useGridStore = create<GridState>()(
             },
 
             setRows: (rows) => {
-                // Construire l'index en O(n) une seule fois au lieu de O(n) à chaque lookup.
-                const rowsIndex = new Map<string, ProductRow>(rows.map(r => [r.codein, r]));
-                set({ rows, rowsIndex, summary: computeSummary(rows, get().draftChanges, get().activeMagasin) });
-            },
-
-            appendRows: (newRows) => {
-                const { rows, rowsIndex, draftChanges, activeMagasin } = get();
-                // O(n) uniquement sur les nouveaux éléments, au lieu de re-calculer les 130k existants
-                const mergedRows = [...rows, ...newRows];
-                newRows.forEach(r => rowsIndex.set(r.codein, r));
-                set({
-                    rows: mergedRows,
-                    rowsIndex,
-                    summary: computeSummary(mergedRows, draftChanges, activeMagasin)
-                });
+                set({ rows, summary: computeSummary(rows, get().draftChanges, get().activeMagasin) });
             },
 
             setDraftGamme: (codein, gamme) => {
-                const { rows, rowsIndex, draftChanges: oldDrafts } = get();
-                // Lookup O(1) via l'index au lieu de O(n) via .find()
-                const originalRow = rowsIndex.get(codein);
+                const { rows, draftChanges: oldDrafts } = get();
+                const originalRow = rows.find(r => r.codein === codein);
                 const originalGamme = originalRow?.codeGamme;
 
                 const draftChanges = { ...oldDrafts };
@@ -163,12 +144,11 @@ export const useGridStore = create<GridState>()(
             },
 
             batchSetDraftGamme: (newChanges) => {
-                const { rows, rowsIndex, draftChanges: oldDrafts } = get();
+                const { rows, draftChanges: oldDrafts } = get();
                 const updatedDrafts = { ...oldDrafts };
 
                 Object.entries(newChanges).forEach(([codein, gamme]) => {
-                    // Lookup O(1) via l'index au lieu de O(n) via .find()
-                    const originalRow = rowsIndex.get(codein);
+                    const originalRow = rows.find(r => r.codein === codein);
                     const originalGamme = originalRow?.codeGamme;
 
                     if (gamme === originalGamme) {