Printing tracking for owned copies and deck art, and an outdated-card-data notice

Owned copies can now be pinned to a printing + finish (nonfoil / foil /
etched), activating the long-dormant library_card_copies table as groups
of identical copies. library_cards.quantity_owned stays authoritative:
groups are a subset of it, and the rest are "unspecified". Tracking more
copies than are unspecified grows ownership to fit; lowering ownership
trims the most recently added groups first. Migration 0006 adds the
group quantity, a unique (card, printing, finish) index, and
deck_cards.preferred_scryfall_id.

A deck slot can show a chosen printing's art, both faces from that
printing, falling back to the default when the id no longer resolves.
It survives quantity/board changes and is kept by duplicate_deck.

UI: the click preview's info tile gets a Printings section when opened
from the Library or a deck (copy groups with steppers, "Add a
printing…", and "Shown in this deck" with Change…/Default), backed by a
printing picker grid. The picker takes Escape in the capture phase so
it closes without closing the preview under it.

Sync: CardEntry.printings (keyed "<scryfall_id>/<finish>") and
DeckCardEntry.printing. Cards now merge field by field with groups per
key, so a quantity edit and a printing added on another device both
survive; merged groups are clamped deterministically. A document is
written as version 2 only once it holds printing data, so older builds
and servers refuse it instead of dropping the data and syncing the loss.

Decklists: "(SET) NUM", optionally "*F*"/"*E*", round-trips through deck
and library export/import. Library export writes a line per group plus
one for unspecified copies.

reference.db printings gain lang and released_at for picker labels and
ordering. When the installed card data lacks any column this build's
reference schema has (found by diffing against the schema applied
in-memory, so no list to maintain), a notice under the top bar offers
Update card data (and Import card data… on phones); "Not now" is
remembered until something more goes missing.

src/App.tsx

@@ -342,6 +342,14 @@ export default function App() {
   // invited exactly what happened: a redundant download click before the
   // real status had even loaded. Distinguish the two explicitly.
   const statusLoaded = status !== null;
+  // Card data built by an older version lacks columns this one reads, so
+  // some features quietly stay off until it's updated. "Not now" is
+  // remembered against exactly what's missing: the notice comes back once a
+  // later version adds something more.
+  const missingColumns = status?.reference_missing_columns ?? [];
+  const outdatedKey = missingColumns.join(",");
+  const [dismissedOutdated, setDismissedOutdated] = usePersistedState("card-data-outdated-dismissed", "");
+  const showOutdated = ready && missingColumns.length > 0 && !progress && dismissedOutdated !== outdatedKey;
   // Mirrors `ready` for the automatic-sync callbacks, which must stay stable
   // across renders (re-creating them would re-arm the listeners below and fire
   // a fresh sync every time card data finished loading).
@@ -632,6 +640,30 @@ export default function App() {
             </div>
           )}
 
+          {showOutdated && (
+            <div className="outdated-bar" role="status">
+              <span className="outdated-bar-message">
+                Your card data was built by an older version of mtgc, so some newer features stay off until you
+                update it.
+              </span>
+              <span className="outdated-bar-actions">
+                <button className="primary" onClick={updateCardData} disabled={busy}>
+                  {ICON_DOWNLOAD}
+                  Update card data
+                </button>
+                {/* A full download is heavy on a phone; copying a fresh
+                    reference.db over from a desktop is the cheaper route. */}
+                {status?.is_mobile && (
+                  <button onClick={importReferenceDb} disabled={busy}>
+                    {ICON_OPEN_LIBRARY}
+                    Import card data…
+                  </button>
+                )}
+                <button onClick={() => setDismissedOutdated(outdatedKey)}>Not now</button>
+              </span>
+            </div>
+          )}
+
           <div className="content">
             {!statusLoaded ? (
               <div className="empty-state">