feat(admin): add search with submit and safe-area layout

Add submit-based search to admin books page and switch borrows
search from debounced to submit-based for consistency. Update
layout headers and nav bars to respect mobile safe-area insets
via CSS custom properties.

src/features/admin/hooks.ts

@@ -17,6 +17,7 @@ export function useAdminSearchBooks(query: string) {
     queryKey: ["admin", "books", "search", query],
     queryFn: () => searchBook(query),
     enabled: query.length > 0,
+    retry: false,
   })
 }
 
@@ -89,6 +90,7 @@ export function useSearchBorrows(query: string) {
     queryKey: ["admin", "borrows", "search", query],
     queryFn: () => searchBorrows(query),
     enabled: query.length > 0,
+    retry: false,
   })
 }
 

src/features/books/hooks.ts

@@ -17,6 +17,7 @@ export function useSearchBooks(query: string) {
     queryKey: ["books", "search", query],
     queryFn: () => searchBook(query),
     enabled: query.length > 0,
+    retry: false,
   })
 }
 

src/features/borrows/hooks.ts

@@ -15,6 +15,7 @@ export function useSearchMyBorrows(query: string) {
     queryKey: ["myBorrows", "search", query],
     queryFn: () => searchMyBorrows(query),
     enabled: query.length > 0,
+    retry: false,
   })
 }