Rework tvOS PeerTube browse and discovery sheets for sidebar layout

Drop nested NavigationStack, .searchable, and close button from the
PeerTube explore view on tvOS; use an inline search field plus Filters
button so focus separates cleanly and the sidebar title is no longer
overlapped. Keep the header visible across empty/error states so the
query can be cleared. Hide the filters and scan-network sheet toolbars
on tvOS, apply filter changes immediately, and add padding plus
scrollClipDisabled so focused rows aren't clipped.

Yattee/Views/Settings/NetworkShareDiscoverySheet.swift

@@ -29,6 +29,11 @@ struct NetworkShareDiscoverySheet: View {
     var body: some View {
         NavigationStack {
             content
+                #if os(tvOS)
+                .scrollClipDisabled()
+                .padding(.horizontal, 40)
+                .padding(.vertical, 40)
+                #else
                 .navigationTitle(String(localized: "discovery.title"))
                 #if os(iOS)
                 .navigationBarTitleDisplayMode(.inline)
@@ -41,6 +46,7 @@ struct NetworkShareDiscoverySheet: View {
                         }
                     }
                 }
+                #endif
                 .onAppear {
                     discoveryService?.startDiscovery()
                 }