fix: several small fixes

src/routes/library/+layout.svelte

@@ -3,11 +3,11 @@
   import { goto } from "$app/navigation";
   import { page } from "$app/stores";
   import { commands } from "$lib/api/bindings";
-  import { platform } from "@tauri-apps/plugin-os";
   import { auth, isAuthenticated, isLoading as isAuthLoading, currentUser } from "$lib/stores/auth";
   import { library } from "$lib/stores/library";
   import { currentMedia, isPlaying, playbackPosition, playbackDuration, shouldShowAudioMiniPlayer } from "$lib/stores/player";
   import { isShuffle, repeatMode, hasNext as hasNextStore, hasPrevious as hasPreviousStore } from "$lib/stores/queue";
+  import { isAndroid } from "$lib/stores/appState";
   import { useScrollGuard } from "$lib/composables/useScrollGuard";
   import Search from "$lib/components/Search.svelte";
   import MiniPlayer from "$lib/components/player/MiniPlayer.svelte";
@@ -31,17 +31,11 @@
   const repeat = $derived($repeatMode);
   const hasNext = $derived($hasNextStore);
   const hasPrevious = $derived($hasPreviousStore);
-  let isAndroid = $state(false);
+  // Platform comes from the shared appState store (set once in the root layout),
+  // so this layout and the root layout never disagree about Android — otherwise
+  // both can suppress their mini players and none appears. See $lib/stores/appState.
 
   onMount(() => {
-    // Detect platform
-    try {
-      const platformName = platform();
-      isAndroid = platformName === "android";
-    } catch (err) {
-      console.error("Platform detection failed:", err);
-    }
-
     return () => {
       scrollGuard.cleanup();
     };
@@ -213,7 +207,7 @@
     <!-- Main content (with padding for bottom nav bar and mini player) -->
     <main
       class="flex-1 overflow-y-auto p-4"
-      style="padding-bottom: {$shouldShowAudioMiniPlayer ? (isAndroid ? '11rem' : '7rem') : '5rem'}; overscroll-behavior: contain"
+      style="padding-bottom: {$shouldShowAudioMiniPlayer ? ($isAndroid ? '11rem' : '7rem') : '5rem'}; overscroll-behavior: contain"
       onscroll={scrollGuard.onScroll}
     >
       {@render children()}
@@ -221,7 +215,7 @@
 
     <!-- Mini Player (only show on non-Android platforms - Android uses global mini player) -->
     <!-- Hide on player page since full player is already there -->
-    {#if !isAndroid && !$page.url.pathname.startsWith('/player/')}
+    {#if !$isAndroid && !$page.url.pathname.startsWith('/player/')}
       <MiniPlayer
         media={$currentMedia}
         isPlaying={$isPlaying}