feat(inbox): add Caixa de Entrada page for managing companion notifications

- Create inbox page with pending items management:
  - InboxCard: displays notification summary with parsed data
  - InboxDetailsDialog: view full notification details
  - ProcessDialog: convert notification to transaction (lancamento)

- Add server actions for inbox operations:
  - getInboxItems: fetch pending inbox items
  - processInboxItem: create lancamento from inbox item
  - discardInboxItem: discard unwanted notifications

- Add navigation link to sidebar under 'Gestão Financeira'
- Add revalidation config for inbox-related paths

app/(dashboard)/caixa-de-entrada/loading.tsx

@@ -0,0 +1,33 @@
+import { Card } from "@/components/ui/card";
+import { Skeleton } from "@/components/ui/skeleton";
+
+export default function Loading() {
+  return (
+    <main className="flex flex-col items-start gap-6">
+      <div className="flex w-full flex-col gap-6">
+        <div className="flex justify-between">
+          <Skeleton className="h-10 w-48" />
+          <Skeleton className="h-10 w-32" />
+        </div>
+        <div className="grid gap-4 md:grid-cols-2 lg:grid-cols-3">
+          {Array.from({ length: 6 }).map((_, i) => (
+            <Card key={i} className="p-4">
+              <div className="space-y-3">
+                <div className="flex justify-between">
+                  <Skeleton className="h-5 w-24" />
+                  <Skeleton className="h-5 w-16" />
+                </div>
+                <Skeleton className="h-4 w-full" />
+                <Skeleton className="h-4 w-3/4" />
+                <div className="flex gap-2 pt-2">
+                  <Skeleton className="h-8 w-20" />
+                  <Skeleton className="h-8 w-20" />
+                </div>
+              </div>
+            </Card>
+          ))}
+        </div>
+      </div>
+    </main>
+  );
+}