android: the first run — a folder to keep music in, and an account to reach the network

Nobody had seen this app on a phone that has just installed it. On Android
the library root is never missing — config.rs falls back to the app's own
sandbox, a real folder nothing else can see — so "no folder yet" cannot be
a null check, and setup_done has never been written by the phone, so every
phone in existence reads as unstamped, Kyle's included. The tour therefore
opens on three clauses, not one: no flag, no saved account, and no records,
read only after the library and the credentials have both answered. Two
cards, skippable, and no password anywhere in it — the Soulseek step goes
to the card on Community and stops.

Every screen that is empty because of those two things now says so with the
row that fixes it: Home (whose copy predated the folder picker), Library →
Albums, Library → Artists, which had no empty state at all, and Search,
where a flat sentence about signing in became the row that does it. A row
goes away because the config moved, so the two doors onto the same folder
tell each other — You re-reads when the tour moves it, the tour's store is
told when You's own picker does — and the all-files row re-reads the grant
when the system screen hands the app back, the way You already did.

You → This phone opens the tour again as a preview that reads the config
and writes nothing, which is the door the phone walk drives on Kyle's own
device. The mock can answer as a fresh install now — an empty database, no
account, no permission, the sandbox root — so the whole thing is walked end
to end, and two commands that had no mock at all (player_control,
open_external) got one on the way past. It is the mock walk's first reload,
which turned up two things a reload does not clear by itself: the player
writes the session back on pagehide, so the fresh block clears it from a
pagehide listener of its own, and the viewport emulation lives on the
DevTools session, so the harness hands it back after the re-attach.

src/mobile/screens/Library.svelte

@@ -4,6 +4,7 @@
        survive a push and a pop. */
     import Icon from "../../components/Icon.svelte";
     import Release from "../Release.svelte";
+    import SetupNote from "../SetupNote.svelte";
     import Cover from "../Cover.svelte";
     import Tracks from "./Tracks.svelte";
     import PlaylistShelf from "../PlaylistShelf.svelte";
@@ -125,6 +126,7 @@
     </div>
     {#if !list.length}
         <div class="stub"><b>Nothing here yet</b>The library on this phone is empty.</div>
+        <SetupNote />
     {:else if view === "grid"}
         <div class="grid2">
             {#each list as a (a.id)}
@@ -142,6 +144,10 @@
     {/if}
 {:else if tab === "artists"}
     <div class="sec-note">{arts.length} artists · {lib.follows.length} followed</div>
+    {#if !arts.length}
+        <div class="stub"><b>No artists yet</b>Every artist with a record in the library on this phone is listed here.</div>
+        <SetupNote />
+    {/if}
     {#each arts as ar (ar.name)}
         <button class="row" onclick={() => push("artist", { name: ar.name }, screenEl)}>
             <span class="art round"><Cover path={ar.art || ar.cover} size={20} /></span>