feat: screenshot app improvement, WIndow Server supports full-screen overlay, Disks app UI improvements

kernel/src/Api/Syscall.cpp

@@ -30,7 +30,7 @@
 #include "Device.hpp"     // SYS_DEVLIST, SYS_DISKINFO
 #include "Input.hpp"      // SYS_INPUT_WAIT
 #include "Storage.hpp"    // SYS_PARTLIST, SYS_DISKREAD, SYS_DISKWRITE
-#include "Window.hpp"     // SYS_WINCREATE, SYS_WINDESTROY, SYS_WINPRESENT, SYS_WINPOLL, SYS_WINENUM, SYS_WINMAP, SYS_WINSENDEVENT, SYS_WINRESIZE, SYS_WINSETSCALE, SYS_WINGETSCALE
+#include "Window.hpp"     // SYS_WINCREATE, SYS_WINDESTROY, SYS_WINPRESENT, SYS_WINPOLL, SYS_WINENUM, SYS_WINMAP, SYS_WINSENDEVENT, SYS_WINRESIZE, SYS_WINSETCURSOR, SYS_WINSETFLAGS, SYS_WINSETSCALE, SYS_WINGETSCALE
 #include "Audio.hpp"      // SYS_AUDIOOPEN, SYS_AUDIOCLOSE, SYS_AUDIOWRITE, SYS_AUDIOCTL
 #include "BluetoothSyscall.hpp" // SYS_BTSCAN, SYS_BTCONNECT, SYS_BTDISCONNECT, SYS_BTLIST, SYS_BTINFO
 #include "IpcSyscall.hpp" // SYS_DUPHANDLE, SYS_WAIT_HANDLE, SYS_STREAM_CREATE, SYS_STREAM_READ, SYS_STREAM_WRITE, SYS_MAILBOX_CREATE, SYS_MAILBOX_SEND, SYS_MAILBOX_RECV, SYS_WAITSET_CREATE, SYS_WAITSET_ADD, SYS_WAITSET_REMOVE, SYS_WAITSET_WAIT, SYS_PROC_OPEN, SYS_SURFACE_CREATE, SYS_SURFACE_MAP, SYS_SURFACE_RESIZE
@@ -297,6 +297,8 @@ namespace Montauk {
                 return (int64_t)Sys_WinGetScale();
             case SYS_WINSETCURSOR:
                 return (int64_t)Sys_WinSetCursor((int)frame->arg1, (int)frame->arg2);
+            case SYS_WINSETFLAGS:
+                return (int64_t)Sys_WinSetFlags((int)frame->arg1, (uint32_t)frame->arg2);
             case SYS_MEMSTATS:
                 if (!UserMemory::Writable<MemStats>(frame->arg1)) return -1;
                 Sys_MemStats((MemStats*)frame->arg1);

kernel/src/Api/Syscall.hpp

@@ -129,6 +129,7 @@ namespace Montauk {
     static constexpr uint64_t SYS_WINSETSCALE  = 65;
     static constexpr uint64_t SYS_WINGETSCALE  = 66;
     static constexpr uint64_t SYS_WINSETCURSOR = 68;
+    static constexpr uint64_t SYS_WINSETFLAGS  = 126;
 
     /* Process.hpp */
     static constexpr uint64_t SYS_PROCLIST    = 61;
@@ -329,8 +330,11 @@ namespace Montauk {
         uint8_t  dirty;
         uint8_t  cursor;    // 0=arrow, 1=resize_h, 2=resize_v
         uint8_t  _pad[2];
+        uint32_t flags;
     };
 
+    static constexpr uint32_t WIN_FLAG_FULLSCREEN = 1u << 0;
+
     struct WinCreateResult {
         int32_t  id;       // -1 on failure
         uint32_t _pad;

kernel/src/Api/WinServer.cpp

@@ -159,6 +159,7 @@ namespace WinServer {
         slot.ownerVa = userVa;
         slot.dirty = false;
         slot.cursor = 0;
+        slot.flags = 0;
 
         int tlen = 0;
         while (title[tlen] && tlen < 63) {
@@ -224,6 +225,7 @@ namespace WinServer {
             info.height = g_slots[i].height;
             info.dirty = g_slots[i].dirty ? 1 : 0;
             info.cursor = g_slots[i].cursor;
+            info.flags = g_slots[i].flags;
             g_slots[i].dirty = false;
             count++;
         }
@@ -336,6 +338,16 @@ namespace WinServer {
         return 0;
     }
 
+    int SetFlags(int windowId, int callerPid, uint32_t flags) {
+        WsGuard guard;
+        if (windowId < 0 || windowId >= MaxWindows) return -1;
+
+        WindowSlot& slot = g_slots[windowId];
+        if (!slot.used || slot.ownerPid != callerPid) return -1;
+        slot.flags = flags & Montauk::WIN_FLAG_FULLSCREEN;
+        return 0;
+    }
+
     int SetScale(int scale) {
         WsGuard guard;
         if (scale < 0) scale = 0;

kernel/src/Api/WinServer.hpp

@@ -24,6 +24,7 @@ namespace WinServer {
         uint64_t ownerVa;               // mapped VA of liveSurface in owner
         bool dirty;
         uint8_t cursor;                 // 0=arrow, 1=resize_h, 2=resize_v
+        uint32_t flags;
     };
 
     int Create(int ownerPid, uint64_t ownerPml4, const char* title, int w, int h,
@@ -39,6 +40,7 @@ namespace WinServer {
                uint64_t& heapNext, uint64_t& outVa);
     void CleanupProcess(int pid);
     int SetCursor(int windowId, int callerPid, int cursor);
+    int SetFlags(int windowId, int callerPid, uint32_t flags);
     int SetScale(int scale);
     int GetScale();
 

kernel/src/Api/Window.hpp

@@ -2,7 +2,7 @@
     * Window.hpp
     * SYS_WINCREATE, SYS_WINDESTROY, SYS_WINPRESENT, SYS_WINPOLL,
     * SYS_WINENUM, SYS_WINMAP, SYS_WINSENDEVENT, SYS_WINRESIZE,
-    * SYS_WINSETSCALE, SYS_WINGETSCALE syscalls
+    * SYS_WINSETCURSOR, SYS_WINSETFLAGS, SYS_WINSETSCALE, SYS_WINGETSCALE syscalls
     * Copyright (c) 2026 Daniel Hammer
 */
 
@@ -75,6 +75,10 @@ namespace Montauk {
         return WinServer::SetCursor(windowId, Sched::GetCurrentPid(), cursor);
     }
 
+    static int Sys_WinSetFlags(int windowId, uint32_t flags) {
+        return WinServer::SetFlags(windowId, Sched::GetCurrentPid(), flags);
+    }
+
     static int Sys_WinSetScale(int scale) {
         return WinServer::SetScale(scale);
     }