feat(market): add Minha Intenções tab with panel, hook, and badge

- Introduced "Minhas Intenções" tab visible only to logged-in users.
- Integrated MyPurchaseIntentionsPanel and useMyPurchaseIntentions hook.
- Added tab badge showing count of pending intentions.
- Extended session API to include user’s main character for downstream features.

lib/hooks/use-listings.ts

@@ -24,6 +24,7 @@ export interface Listing {
   image_url?: string | null;
   item_category?: string | null;
   seller_character_name?: string | null;
+  has_pending_intention_for_current_user?: boolean;
 }
 
 interface ListingsResponse {