Add screen recording, crop, and a Cap-style result window

Recording: Ctrl+Shift+Cmd+R (or the menu) opens the same selection
flow — a marquee records that region, clicking a window records it
(following moves). Video is H.264 .mov at 60fps via SCStream ->
AVAssetWriter with the cursor included, auto-saved to ~/Movies and
revealed in Finder on stop. A red border and a floating timer/stop bar
show during recording, both excluded from the video. Audio is wired
behind a flag for later.

The result window gains a Crop button (crop to the selection;
annotations translate and stay editable) and is restyled after Cap:
sliding-pill Screenshot/Text switcher, capsule buttons in Cap blue,
circular icon buttons, and the content on a rounded card — light and
dark.

Generated with OpenCode

Assisted-by: Kimi:k3

Sources/Kapture/OverlayView.swift

@@ -97,9 +97,14 @@ final class OverlayView: NSView {
         }
 
         // Esc hint — the only way out once clicks are consumed by the tap.
-        let hint = frozenImage != nil
-            ? "Frozen screen · drag to select · Esc to cancel"
-            : "Drag to select · hover + click a window to capture it · Esc to cancel"
+        let hint: String
+        if controller?.isRecordingMode == true {
+            hint = "Drag to select · hover + click a window to record · Esc to cancel"
+        } else if frozenImage != nil {
+            hint = "Frozen screen · drag to select · Esc to cancel"
+        } else {
+            hint = "Drag to select · hover + click a window to capture it · Esc to cancel"
+        }
         let hintAttrs: [NSAttributedString.Key: Any] = [
             .font: NSFont.monospacedSystemFont(ofSize: 12, weight: .medium),
             .foregroundColor: NSColor.white.withAlphaComponent(0.85),