Enable SwiftLint rule: empty_count

Prefer `.isEmpty` over comparing `.count` to zero.
1 auto-fixed violation in `SPNoteListViewController+Extensions.swift`.

Part of the Orchard SwiftLint rollout campaign.

---

Generated with the help of Claude Code, https://claude.ai/code

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

Author: mokagio

.swiftlint.yml

@@ -23,6 +23,9 @@ only_rules:
 
   - duplicate_imports
 
+  # Prefer checking `isEmpty` over comparing `count` to zero.
+  - empty_count
+
   # Arguments can be omitted when matching enums with associated types if they
   # are not used.
   - empty_enum_arguments

Simplenote/Classes/SPNoteListViewController+Extensions.swift

@@ -398,7 +398,7 @@ extension SPNoteListViewController {
             trashButton.isEnabled = false
             return
         }
-        trashButton.isEnabled = selectedRows.count > 0
+        trashButton.isEnabled = !selectedRows.isEmpty
     }
 }