android: a peer in full — their card, their interests, and what they have that you don't

The peer sheet's new "About this user" row opens a screen of its own: the
card their client serves (their own words, their picture, the upload slot
and the queue), the likes and hates they declared, and the comparison this
phone makes of their share against the library. The comparison is the
point of opening a stranger — every record they have by an artist in your
library that you don't, each row opening the search that finds it, and a
way to forget the whole comparison again. Nothing is uploaded to work it
out. Their picture opens in the artwork viewer, which now takes a data:
key beside a library path and an https URL.

src/mobile/HalfSheet.svelte

@@ -511,6 +511,9 @@
                     {@render row("download", "Save this folder to library", "every file, as it is", act(() => saveGroup(g)))}
                     <div class="sheet-hair"></div>
                 {/if}
+                {#if !(top().n === "peer" && top().c.username === u)}
+                    {@render row("users", "About this user", "their card, and what they have that you don't", act(() => push("peer", { username: u })))}
+                {/if}
                 {#if !(top().n === "browse" && top().c.username === u)}
                     {@render row("folder-open", "Browse their files", "everything they share", act(() => push("browse", { username: u })))}
                 {/if}