Fix transactions page crash when no accounts exist (#1453)

Skip the accessible_account_ids filter when the array is empty, preventing
Rails from creating a "none" relation that causes .take to return nil.
An empty [] is truthy in Ruby, so `if accessible_account_ids` was applying
a WHERE account_id IN () clause that matched nothing.

Fixes #1452

Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>

app/models/transaction/search.rb

@@ -28,6 +28,9 @@ class Transaction::Search
       # This already joins entries + accounts. To avoid expensive double-joins, don't join them again (causes full table scan)
       query = family.transactions.merge(Entry.excluding_split_parents)
 
+      # Scope to accessible accounts when provided
+      query = query.where(entries: { account_id: accessible_account_ids }) if accessible_account_ids&.any?
+
       query = apply_active_accounts_filter(query, active_accounts_only)
       query = apply_category_filter(query, categories)
       query = apply_type_filter(query, types)