feat(app): 활성 창 캡쳐·캡쳐 목적지 선택·단축키 Ctrl+Alt 재배치 + UX 손질

- Ctrl+Alt+A/Z 맨 앞 창 통째 캡쳐(DWM 확장 프레임 경계), S/X 드래그 캡쳐. A/S 새 대화, Z/X 마지막 대화
- 캡쳐 후 창을 확실히 앞으로(AttachThreadInput), capture.image 에 목적지 path 실어 그 Composer 만 소비
- 드래그 선택영역 원본 밝기·더블버퍼(번쩍임) — code-assistant-v2 복사본에서 이식
- 단축키 Ctrl+Alt+Q/W: Eclipse·ADT·SAP GUI 바인딩 목록 대조해 비어 있는 조합으로
- 버튼 cursor:pointer(Tailwind v4), 가운데 스피너, 스니펫→챗 버튼, 스니펫 검색창 높이 84→88

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

2_frontend/src/lib/bridge/bridgeNavigate.test.ts

@@ -29,15 +29,20 @@ describe("bridgeNavigate", () => {
 
     await emit("bridge", { type: "navigate", path: "/snippet" })
     await emit("bridge", { type: "paste.target", name: "메모장", app: "notepad" })
-    await emit("bridge", { type: "capture.image", dataUrl: "data:image/png;base64,abc" })
+    await emit("bridge", {
+      type: "capture.image",
+      path: "/snap/new",
+      dataUrl: "data:image/png;base64,abc",
+    })
 
     expect(navigate).toHaveBeenCalledWith("/snippet")
     expect(onNavigate).toHaveBeenCalledTimes(1)
     expect(getLastPasteTarget()).toEqual({ name: "메모장", app: "notepad" })
     expect(onPasteTarget).toHaveBeenCalledTimes(1)
     expect(onCapture).toHaveBeenCalledTimes(1)
-    expect(consumePendingCaptureImage()).toBe("data:image/png;base64,abc")
-    expect(consumePendingCaptureImage()).toBe("")
+    expect(consumePendingCaptureImage("/snap/s/old")).toBe("")
+    expect(consumePendingCaptureImage("/snap/new")).toBe("data:image/png;base64,abc")
+    expect(consumePendingCaptureImage("/snap/new")).toBe("")
 
     window.removeEventListener("bridge:navigate", onNavigate)
     window.removeEventListener("bridge:pasteTarget", onPasteTarget)

2_frontend/src/lib/bridge/bridgeNavigate.ts

@@ -9,7 +9,7 @@ export interface PasteTarget {
 
 let navigateFn: NavigateFn | null = null
 let lastPasteTarget: PasteTarget = { name: "", app: "" }
-let pendingCaptureImage = ""
+let pendingCaptureImage: { path: string; dataUrl: string } | null = null
 
 /** 앱 루트에서 useNavigate() 감싼 콜백을 등록함. */
 export function setBridgeNavigate(fn: NavigateFn | null) {
@@ -21,10 +21,11 @@ export function getLastPasteTarget(): PasteTarget {
   return lastPasteTarget
 }
 
-/** 마지막 캡처 이미지를 한 번만 소비함. */
-export function consumePendingCaptureImage(): string {
-  const dataUrl = pendingCaptureImage
-  pendingCaptureImage = ""
+/** 지정한 대화에 도착한 마지막 캡처 이미지를 한 번만 소비함. */
+export function consumePendingCaptureImage(path: string): string {
+  if (pendingCaptureImage?.path !== path) return ""
+  const { dataUrl } = pendingCaptureImage
+  pendingCaptureImage = null
   return dataUrl
 }
 
@@ -41,11 +42,9 @@ function handleBridgeMessage(data: {
     return
   }
 
-  if (data.type === "capture.image") {
-    pendingCaptureImage = data.dataUrl ?? ""
-    window.dispatchEvent(
-      new CustomEvent("bridge:captureImage", { detail: { dataUrl: pendingCaptureImage } })
-    )
+  if (data.type === "capture.image" && data.path) {
+    pendingCaptureImage = { path: data.path, dataUrl: data.dataUrl ?? "" }
+    window.dispatchEvent(new CustomEvent("bridge:captureImage", { detail: pendingCaptureImage }))
     return
   }