Add encrypted LAN mouse and keyboard sharing with four-edge handoff

src/lan.h

@@ -4,7 +4,7 @@
 
 namespace ks
 {
-// Local-only discovery and pairing. No input/clipboard receiver is exposed yet.
+// Discovery, pairing and optional encrypted input within the resident process.
 class LanService
 {
     struct Impl;
@@ -13,5 +13,11 @@ class LanService
     explicit LanService(const std::filesystem::path &);
     ~LanService();
     Bytes command(const Bytes &);
+    bool inputEnabled() const;
+    bool tickInput(bool allowEnter = true);
+    bool keyboard(const KBDLLHOOKSTRUCT &, bool down);
+    bool mouse(UINT, const MSLLHOOKSTRUCT &, bool allowEnter);
+    bool takeInputChange();
+    void cancelInput();
 };
 }