Add a "not owned" quick filter and horizontal tile view to Card Search

"Not owned" moves into the shared Quick filters icon-toggle row (hidden on
the Library tab, where it'd always be a no-op since that view is owned-only
already) instead of a standalone button.

Tiles view gains a "Horizontal" toggle that rotates actually-horizontal
cards (Battles, Planes, Phenomena) into their natural landscape orientation
via a container-query-sized wrapper, spanning two grid columns so the
rotated card isn't squeezed into a single portrait column's width and left
too small to read.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

crates/mtgc-core/src/model.rs

@@ -341,6 +341,12 @@ pub struct LibraryFilter {
     pub power_max: Option<f64>,
     pub toughness_min: Option<f64>,
     pub toughness_max: Option<f64>,
+    /// Only cards with zero owned copies. Meaningless against
+    /// [`Catalog::search_library`] (which already only returns owned cards),
+    /// so it's only honored by [`Catalog::search_reference`] — the Card
+    /// Search tab's "Not owned" quick filter.
+    #[serde(default)]
+    pub not_owned: bool,
 }
 
 #[cfg(test)]