fix: Show alerts below stats normally, fix usage cost calculation

- Alerts shown below QuickStats without hover reveal
- Alerts also listed after usage analytics section
- Usage cost now shows cost of material consumed (unit cost * usage)
  instead of all-time purchase total which was misleading

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

client/src/pages/home/components/AlertCards.tsx

@@ -1,7 +1,6 @@
-import { ExclamationCircleOutlined, PrinterOutlined, DashboardOutlined, WarningOutlined } from "@ant-design/icons";
+import { ExclamationCircleOutlined, PrinterOutlined, DashboardOutlined } from "@ant-design/icons";
 import { useList, useTranslate } from "@refinedev/core";
-import { Badge, Card, Col, Row, theme, Typography } from "antd";
-import { useState } from "react";
+import { Badge, Card, Col, Row, theme } from "antd";
 import { Link } from "react-router";
 import { ISpool } from "../../spools/model";
 import { IPrintJob } from "../../spools/model";
@@ -41,13 +40,12 @@ function AlertCard({ icon, label, count, to, color, loading }: AlertCardProps) {
 }
 
 interface AlertCardsProps {
-  reveal?: boolean;
+  compact?: boolean;
 }
 
-export function AlertCards({ reveal }: AlertCardsProps) {
+export function AlertCards({ compact }: AlertCardsProps) {
   const t = useTranslate();
   const { token } = useToken();
-  const [hovered, setHovered] = useState(false);
 
   // Low stock spools
   const { result: lowStockResult, query: lowStockQuery } = useList<ISpool>({
@@ -111,42 +109,8 @@ export function AlertCards({ reveal }: AlertCardsProps) {
 
   if (visibleAlerts.length === 0) return null;
 
-  const totalAlertCount = visibleAlerts.reduce((sum, a) => sum + a.count, 0);
-
-  if (reveal) {
-    return (
-      <div
-        onMouseEnter={() => setHovered(true)}
-        onMouseLeave={() => setHovered(false)}
-        style={{ marginTop: 8 }}
-      >
-        <Typography.Text
-          type="secondary"
-          style={{ fontSize: 12, cursor: "pointer", display: "flex", alignItems: "center", gap: 4 }}
-        >
-          <WarningOutlined />
-          {totalAlertCount} {totalAlertCount === 1 ? "alert" : "alerts"}
-        </Typography.Text>
-        <div
-          style={{
-            maxHeight: hovered ? 200 : 0,
-            overflow: "hidden",
-            transition: "max-height 0.2s ease",
-            marginTop: hovered ? 8 : 0,
-          }}
-        >
-          <Row gutter={[8, 8]}>
-            {visibleAlerts.map((alert, i) => (
-              <AlertCard key={i} {...alert} />
-            ))}
-          </Row>
-        </div>
-      </div>
-    );
-  }
-
   return (
-    <Row gutter={[12, 12]} style={{ marginBottom: 16 }}>
+    <Row gutter={[compact ? 8 : 12, compact ? 8 : 12]} style={{ marginTop: compact ? 8 : 16 }}>
       {visibleAlerts.map((alert, i) => (
         <AlertCard key={i} {...alert} />
       ))}

client/src/pages/home/components/UsageAnalytics.tsx

@@ -122,18 +122,21 @@ export function UsageAnalytics() {
               <div style={{ display: "flex", flexWrap: "wrap", gap: 8 }}>
                 {materialData.map((m) => {
                   const costInfo = costData?.cost_by_material?.find((c) => c.material === m.material);
+                  // Calculate cost of material used based on unit cost (cost per gram)
+                  const costPerGram = costInfo && costInfo.total_weight > 0 ? costInfo.total_cost / costInfo.total_weight : null;
+                  const usageCost = costPerGram != null ? costPerGram * m.weight_used : null;
                   return (
                     <Card size="small" key={m.material} style={{ minWidth: 120 }}>
                       <Typography.Text strong>{m.material}</Typography.Text>
                       <br />
                       <Typography.Text type="secondary">
-                        {t("home.analytics.used")}: {m.weight_used >= 1000 ? `${(m.weight_used / 1000).toFixed(2)} kg` : `${m.weight_used.toFixed(0)} g`}
+                        {m.weight_used >= 1000 ? `${(m.weight_used / 1000).toFixed(2)} kg` : `${m.weight_used.toFixed(0)} g`}
                       </Typography.Text>
-                      {costInfo && (
+                      {usageCost != null && (
                         <>
                           <br />
                           <Typography.Text type="secondary">
-                            {t("home.analytics.spent")}: {currencyFormatter.format(costInfo.total_cost)}
+                            {currencyFormatter.format(usageCost)}
                           </Typography.Text>
                         </>
                       )}

client/src/pages/home/index.tsx

@@ -134,7 +134,7 @@ export const Home: React.FC<IResourceComponentsProps> = () => {
             </Col>
           </Row>
           <QuickStats compact />
-          <AlertCards reveal />
+          <AlertCards compact />
         </Col>
       </Row>
 
@@ -171,6 +171,9 @@ export const Home: React.FC<IResourceComponentsProps> = () => {
 
       {/* Usage analytics & insights */}
       <UsageAnalytics />
+
+      {/* Alerts */}
+      <AlertCards />
     </Content>
   );
 };