refactor: rename ManaDeck to Cards across entire monorepo

Rename the flashcard/deck management app from ManaDeck to Cards:
- Directory: apps/manadeck → apps/cards, packages/manadeck-database → packages/cards-database
- Packages: @manadeck/* → @cards/*, @manacore/manadeck-database → @manacore/cards-database
- Domain: manadeck.mana.how → cards.mana.how
- Storage: manadeck-storage → cards-storage
- Database: manadeck → cards
- All shared packages, infra configs, services, i18n, and docs updated
- 244 files changed, zero remaining manadeck references

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

scripts/mac-mini/build-landings.sh

@@ -23,7 +23,7 @@ declare -A LANDINGS=(
     ["zitare"]="apps/zitare/apps/landing"
     ["presi"]="apps/presi/apps/landing"
     ["clock"]="apps/clock/apps/landing"
-    ["manadeck"]="apps/manadeck/apps/landing"
+    ["cards"]="apps/cards/apps/landing"
     ["nutriphi"]="apps/nutriphi/apps/landing"
     ["citycorners"]="apps/citycorners/apps/landing"
 )

scripts/mac-mini/deploy-v2.sh

@@ -92,7 +92,7 @@ sleep 5
 
 # Create all needed databases
 for db in mana_auth mana_credits mana_user mana_subscriptions mana_analytics mana_sync \
-          chat todo calendar contacts storage manadeck mukke nutriphi planta \
+          chat todo calendar contacts storage cards mukke nutriphi planta \
           questions traces context citycorners photos presi skilltree; do
     docker compose -f "$COMPOSE_FILE" exec -T postgres \
         psql -U postgres -c "CREATE DATABASE $db;" 2>/dev/null || true