Initial commit: RustDesk 1.4.7 macOS desktop port

- Filled empty libs/hbb_common/ submodule (cloned from rustdesk/hbb_common)
- Patched Flutter 3.44 / Dart 3.12 compatibility:
  * flutter/lib/generated_bridge.dart: asTypedList with cast<>, DartPort=Int64
  * flutter/lib/common.dart: DialogTheme->DialogThemeData, TabBarTheme->TabBarThemeData
  * flutter/pubspec.yaml: extended_text 14.0.0->15.0.2, google_fonts override 5.0.0
  * flutter/macos/Runner/Configs/Release.xcconfig: EXCLUDED_ARCHS=x86_64
- Build verified: cargo check + cargo build --features flutter + cargo build --release --features flutter
- Verified flutter build macos --debug and --release both produce working .app
- Verified .dmg installer (27MB arm64) created via hdiutil
- Build deps: Xcode 26.5, CocoaPods 1.16.2, Flutter 3.44, VCPKG arm64-osx

libs/scrap/examples/screenshot.rs

@@ -0,0 +1,141 @@
+extern crate repng;
+extern crate scrap;
+
+use std::fs::File;
+use std::io::ErrorKind::WouldBlock;
+use std::thread;
+use std::time::Duration;
+
+use scrap::{Capturer, Display, Frame, TraitCapturer, TraitPixelBuffer};
+
+fn main() {
+    let n = Display::all().unwrap().len();
+    for i in 0..n {
+        record(i);
+    }
+}
+
+fn get_display(i: usize) -> Display {
+    Display::all().unwrap().remove(i)
+}
+
+fn record(i: usize) {
+    let one_second = Duration::new(1, 0);
+    let one_frame = one_second / 60;
+
+    for d in Display::all().unwrap() {
+        println!("{:?} {} {}", d.origin(), d.width(), d.height());
+    }
+
+    let display = get_display(i);
+    let mut capturer = Capturer::new(display).expect("Couldn't begin capture.");
+    let (w, h) = (capturer.width(), capturer.height());
+
+    loop {
+        // Wait until there's a frame.
+
+        let frame = match capturer.frame(Duration::from_millis(0)) {
+            Ok(frame) => frame,
+            Err(error) => {
+                if error.kind() == WouldBlock {
+                    // Keep spinning.
+                    thread::sleep(one_frame);
+                    continue;
+                } else {
+                    panic!("Error: {}", error);
+                }
+            }
+        };
+        let Frame::PixelBuffer(frame) = frame else {
+            return;
+        };
+        let buffer = frame.data();
+        println!("Captured data len: {}, Saving...", buffer.len());
+
+        // Flip the BGRA image into a RGBA image.
+
+        let mut bitflipped = Vec::with_capacity(w * h * 4);
+        let stride = buffer.len() / h;
+
+        for y in 0..h {
+            for x in 0..w {
+                let i = stride * y + 4 * x;
+                bitflipped.extend_from_slice(&[buffer[i + 2], buffer[i + 1], buffer[i], 255]);
+            }
+        }
+
+        // Save the image.
+
+        let name = format!("screenshot{}_1.png", i);
+        repng::encode(
+            File::create(name.clone()).unwrap(),
+            w as u32,
+            h as u32,
+            &bitflipped,
+        )
+        .unwrap();
+
+        println!("Image saved to `{}`.", name);
+        break;
+    }
+
+    drop(capturer);
+    let display = get_display(i);
+    let mut capturer = Capturer::new(display).expect("Couldn't begin capture.");
+    let (w, h) = (capturer.width(), capturer.height());
+
+    loop {
+        // Wait until there's a frame.
+
+        let frame = match capturer.frame(Duration::from_millis(0)) {
+            Ok(frame) => frame,
+            Err(error) => {
+                if error.kind() == WouldBlock {
+                    // Keep spinning.
+                    thread::sleep(one_frame);
+                    continue;
+                } else {
+                    panic!("Error: {}", error);
+                }
+            }
+        };
+        let Frame::PixelBuffer(frame) = frame else {
+            return;
+        };
+        let buffer = frame.data();
+        println!("Captured data len: {}, Saving...", buffer.len());
+
+        let mut raw = Vec::new();
+        unsafe {
+            scrap::ARGBToRAW(
+                buffer.as_ptr(),
+                frame.stride()[0] as _,
+                (&mut raw).as_mut_ptr(),
+                (w * 3) as _,
+                w as _,
+                h as _,
+            )
+        };
+
+        let mut bitflipped = Vec::with_capacity(w * h * 4);
+        let stride = raw.len() / h;
+
+        for y in 0..h {
+            for x in 0..w {
+                let i = stride * y + 3 * x;
+                bitflipped.extend_from_slice(&[raw[i], raw[i + 1], raw[i + 2], 255]);
+            }
+        }
+        let name = format!("screenshot{}_2.png", i);
+        repng::encode(
+            File::create(name.clone()).unwrap(),
+            w as u32,
+            h as u32,
+            &bitflipped,
+        )
+        .unwrap();
+
+        println!("Image saved to `{}`.", name);
+        break;
+    }
+}