Add a Card Search tab and fix horizontal-card (Battle/Plane) preview orientation

Card Search browses the whole downloaded card universe (not just owned
cards), reusing the Library tab's filter/group/sort/list/tiles UI; results
show ownership and offer quick "own" and "add to deck" actions.

Battles, Planes, and Phenomena store their Scryfall image portrait-shaped
with the content itself rotated, so hover/click previews now detect this
(a new `horizontal` flag threaded through ingest and every card query, with
graceful fallback for a reference.db built before the column existed) and
rotate the image back into place. Single-faced and non-DFC cases are
verified fixed; a double-faced Battle's front face still needs another pass.

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

src/App.tsx

@@ -14,9 +14,10 @@ import {
 import { CommandPalette } from "./CommandPalette";
 import { CardEntry } from "./views/CardEntry";
 import { LibraryBrowser } from "./views/LibraryBrowser";
+import { CardSearch } from "./views/CardSearch";
 import { DeckView } from "./views/DeckView";
 
-type Tab = "add" | "library" | "decks";
+type Tab = "add" | "library" | "search" | "decks";
 
 const svg = (children: ReactNode, size = 20) => (
   <svg
@@ -94,6 +95,16 @@ const NAV: { id: Tab; label: string; icon: ReactNode }[] = [
       </>,
     ),
   },
+  {
+    id: "search",
+    label: "Card Search",
+    icon: svg(
+      <>
+        <circle cx="11" cy="11" r="7" />
+        <line x1="21" y1="21" x2="16.65" y2="16.65" />
+      </>,
+    ),
+  },
   {
     id: "decks",
     label: "Decks",
@@ -439,6 +450,8 @@ export default function App() {
               <CardEntry />
             ) : tab === "library" ? (
               <LibraryBrowser onOfferUndo={offerUndo} />
+            ) : tab === "search" ? (
+              <CardSearch onOfferUndo={offerUndo} />
             ) : (
               <DeckView refreshSignal={deckRefreshSignal} />
             )}