feat(home): tap opens detail, long-press plays from home cards

Home carousel cards route a tap to the item's detail / Episode Focus
View and a ~500ms long-press to a confirm-then-play flow. MediaCard gains
an onLongPress prop with pointer-based detection (cancelled on >10px move
so carousel scroll is unaffected, trailing click suppressed). Episode
taps route to /library/<seriesId>?episode=<id>; the bare-episode detail
page links back to its parent series/season.

TRACES: UR-058 | DR-087

src/routes/+page.svelte

@@ -56,18 +56,47 @@
     previousServerReachable = serverReachable;
   });
 
+  // Tap → detail page. Non-playable containers already routed to /library; now
+  // movies and episodes go to their detail page too instead of playing straight
+  // away. Channel leaves (no detail page) still go direct to the player.
+  // TRACES: UR-058 | DR-087
   function handleItemClick(item: MediaItem) {
     switch (item.kind) {
-      case "series":
-      case "season":
-      case "album":
-      case "artist":
-      case "folder":
-      case "channel":
-        goto(`/library/${item.id}`);
+      case "channelItem":
+      case "liveChannel":
+        goto(`/player/${item.id}`);
+        break;
+      case "episode":
+        // An episode is never browsed as a bare Episode page — it opens in its
+        // series' Episode Focus View so the series context loads (ux-flows §5B.1).
+        if (item.seriesId) {
+          goto(`/library/${item.seriesId}?episode=${item.id}`);
+        } else {
+          goto(`/library/${item.id}`);
+        }
         break;
       default:
-        goto(`/player/${item.id}`);
+        goto(`/library/${item.id}`);
+        break;
+    }
+  }
+
+  // Long press → play immediately, confirming first so an accidental hold on a
+  // half-watched item doesn't blow away the user's spot without warning.
+  // TRACES: UR-058 | DR-087
+  function handleItemLongPress(item: MediaItem) {
+    switch (item.kind) {
+      case "movie":
+      case "episode":
+      case "channelItem":
+      case "liveChannel":
+        if (confirm(`Play "${item.name}" now?`)) {
+          goto(`/player/${item.id}`);
+        }
+        break;
+      default:
+        // Containers (series/season/album/…) have no single "play now" target.
+        goto(`/library/${item.id}`);
         break;
     }
   }
@@ -145,6 +174,7 @@
         title="Next Movie"
         items={resumeMovies}
         onItemClick={handleItemClick}
+        onItemLongPress={handleItemLongPress}
       />
     {/if}
 
@@ -154,6 +184,7 @@
         title="Next Episode"
         items={nextUpItems}
         onItemClick={handleItemClick}
+        onItemLongPress={handleItemLongPress}
       />
     {/if}
 
@@ -163,6 +194,7 @@
         title="Recently Listened"
         items={recentlyPlayedAudio}
         onItemClick={handleItemClick}
+        onItemLongPress={handleItemLongPress}
       />
     {/if}
 
@@ -172,6 +204,7 @@
         title="Continue Watching"
         items={resumeItems}
         onItemClick={handleItemClick}
+        onItemLongPress={handleItemLongPress}
       />
     {/if}
 
@@ -181,6 +214,7 @@
         title="Recently Added"
         items={latestItems}
         onItemClick={handleItemClick}
+        onItemLongPress={handleItemLongPress}
       />
     {/if}