feat(app): implement basic function

General
- 配置界面支持配置对象存储桶
- 快捷键进入截图
- 一键上传截图 & 复制截图链接

MacOS
- 状态栏指示器和应用图标

internal/infrastructure/display/display_darwin.go

@@ -0,0 +1,41 @@
+//go:build darwin
+
+package display
+
+/*
+#cgo LDFLAGS: -framework CoreGraphics -framework Foundation
+#include <CoreGraphics/CoreGraphics.h>
+
+// readPrimaryDisplay fills the four out-params with:
+//   - cssW / cssH    : logical (point) dimensions of the main display
+//   - pxW  / pxH     : physical (device-pixel) dimensions
+// Using CGDisplayBounds for points and CGDisplayPixelsWide/High for pixels
+// is the canonical way to derive the backing scale on macOS without
+// bringing AppKit into the build (we do not want to link Cocoa here).
+static void readPrimaryDisplay(int* cssW, int* cssH, int* pxW, int* pxH) {
+    CGDirectDisplayID id = CGMainDisplayID();
+    CGRect bounds = CGDisplayBounds(id);
+    *cssW = (int)bounds.size.width;
+    *cssH = (int)bounds.size.height;
+    *pxW  = (int)CGDisplayPixelsWide(id);
+    *pxH  = (int)CGDisplayPixelsHigh(id);
+}
+*/
+import "C"
+
+// Primary returns the geometry of the main display. The CGo call has no
+// failure path — the OS always reports a main display whenever there is at
+// least one attached, which is implied for any GUI process.
+func Primary() Info {
+	var cssW, cssH, pxW, pxH C.int
+	C.readPrimaryDisplay(&cssW, &cssH, &pxW, &pxH)
+	scale := 1.0
+	if cssW > 0 {
+		scale = float64(pxW) / float64(cssW)
+	}
+	return Info{
+		CSSWidth:  int(cssW),
+		CSSHeight: int(cssH),
+		Scale:     scale,
+	}
+}