feat: fix start screen window dimensions

Sources/App/TerebiApp.swift

@@ -513,6 +513,7 @@ final class PlayerModel: ObservableObject {
             }
             return
         }
+        if fileName == nil { configureStartWindow(showing: false) }
         transition.acceptOpen(revision: revision, source: source, change: change, savedPosition: savedPosition)
         queuePlaybackRevision = queue.currentID == nil ? nil : player_get_state(handle).revision
         queueCompletionHandled = false
@@ -710,6 +711,7 @@ final class PlayerModel: ObservableObject {
         isSeeking = false
         window?.representedURL = nil
         window?.title = "Terebi"
+        configureStartWindow(showing: true)
         revealControls()
         systemPlayback?.update()
     }
@@ -835,9 +837,26 @@ final class PlayerModel: ObservableObject {
         }
         compactWindow.attach(window)
         updateWindowState()
+        if fileName == nil { configureStartWindow(showing: true) }
         fitVideoWindow()
     }
 
+    private func configureStartWindow(showing: Bool) {
+        guard let window else { return }
+        if showing {
+            let size = NSSize(width: 640, height: 400)
+            window.resizeIncrements = NSSize(width: 1, height: 1)
+            window.contentMinSize = size
+            window.contentMaxSize = size
+            window.setContentSize(size)
+            window.styleMask.remove(.resizable)
+        } else {
+            window.styleMask.insert(.resizable)
+            window.contentMaxSize = NSSize(width: CGFloat.greatestFiniteMagnitude, height: CGFloat.greatestFiniteMagnitude)
+            window.contentMinSize = NSSize(width: 400, height: 240)
+        }
+    }
+
     func updateWindowState() {
         guard let window else { return }
         isFullScreen = window.styleMask.contains(.fullScreen)