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/CommandPalette.tsx

@@ -2,7 +2,7 @@ import { useEffect, useRef, useState } from "react";
 import { api, CardRef, Deck } from "./api";
 import { DialogFrame, useClickPreview } from "./components";
 
-type Tab = "add" | "library" | "decks";
+type Tab = "add" | "library" | "search" | "decks";
 
 interface PaletteItem {
   key: string;
@@ -93,6 +93,7 @@ export function CommandPalette({
     ...(undo ? [{ key: "undo", label: `Undo: ${undo.message}`, run: onRunUndo }] : []),
     { key: "nav-add", label: "Go to Add Cards", run: () => onNavigate("add") },
     { key: "nav-library", label: "Go to Library", run: () => onNavigate("library") },
+    { key: "nav-search", label: "Go to Card Search", run: () => onNavigate("search") },
     { key: "nav-decks", label: "Go to Decks", run: () => onNavigate("decks") },
     { key: "update-card-data", label: "Update card data", run: onUpdateCardData },
     { key: "open-library", label: "Switch library file…", run: onOpenLibrary },