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/app/api/grid/rows/route.ts

@@ -1,49 +0,0 @@
-import { NextRequest, NextResponse } from "next/server";
-import { getProductRows } from "@/features/grid/api/get-product-rows";
-import { auth } from "@/lib/auth";
-
-export async function GET(request: NextRequest) {
-    const session = await auth();
-    if (!session) {
-        return NextResponse.json({ error: "Non autorisé" }, { status: 401 });
-    }
-
-    const { searchParams } = request.nextUrl;
-    const codeFournisseur = searchParams.get("fournisseur");
-
-    if (!codeFournisseur) {
-        return NextResponse.json({ error: "Paramètre 'fournisseur' requis" }, { status: 400 });
-    }
-
-    const page     = parseInt(searchParams.get("page")     ?? "0",   10);
-    const pageSize = parseInt(searchParams.get("pageSize") ?? "200", 10);
-    const offsetRaw = searchParams.get("offset");
-    const offset   = offsetRaw ? parseInt(offsetRaw, 10) : undefined;
-    const search   = searchParams.get("search")  ?? undefined;
-    const gamme    = searchParams.get("gamme")   ?? undefined;
-    const code3    = searchParams.get("code3")   ?? undefined;
-    const magasin  = searchParams.get("magasin") ?? undefined;
-
-    try {
-        const result = await getProductRows({
-            codeFournisseur,
-            magasin,
-            page:     isNaN(page)     ? 0   : page,
-            pageSize: isNaN(pageSize) ? 200 : pageSize,
-            offset:   offset !== undefined && !isNaN(offset) ? offset : undefined,
-            search,
-            gamme:    gamme  || null,
-            code3:    code3  || null,
-        });
-
-        return NextResponse.json(result, {
-            status: 200,
-            headers: {
-                "Cache-Control": "private, max-age=30, stale-while-revalidate=60",
-            },
-        });
-    } catch (error) {
-        console.error("[GET /api/grid/rows] Error:", error);
-        return NextResponse.json({ error: "Erreur lors de la récupération des données" }, { status: 500 });
-    }
-}