rename: user-facing product name Shotdeck -> Redline; legacy PDFs still recognized

Sources/Shotdeck/main.swift

@@ -27,7 +27,7 @@ struct ShotdeckApp: App {
                     Text(count).font(.system(size: 11, weight: .semibold))
                 }
             }
-            .accessibilityLabel("Shotdeck")
+            .accessibilityLabel("Redline")
         }
         .menuBarExtraStyle(.window)
     }
@@ -60,7 +60,7 @@ final class AppDelegate: NSObject, NSApplicationDelegate {
             // Safe: temp-dir creation for a path this process controls cannot legitimately fail.
             let fallback = try! AppSupportPaths(root: fallbackRoot, outbox: tmp, watchFolder: tmp)
             let model = try! makeModel(paths: fallback)
-            model.setStatus("Shotdeck could not access its storage folder. Captures will not persist.")
+            model.setStatus("Redline could not access its storage folder. Captures will not persist.")
             return model
         }
     }