feat(desktop): P 键暂停帮助页

P 键改为打开暂停帮助页（完整键位说明），打开时暂停模拟并保留原控制状态，返回游戏时精确恢复（速度/暂停原状）；常驻 HUD 不放全键位清单。MenuState 新增 enterPauseHelp/exitPauseHelp 纯函数与回归测试。

1 files changed, 16 insertions, 0 deletions

diff --git a/src/LivingVillage.Desktop.Tests/PrototypeTests.fs b/src/LivingVillage.Desktop.Tests/PrototypeTests.fs
index f1f4aed..524573f 100644
--- a/src/LivingVillage.Desktop.Tests/PrototypeTests.fs
+++ b/src/LivingVillage.Desktop.Tests/PrototypeTests.fs
@@ -203,6 +203,22 @@ type PrototypeTests () =
         Assert.IsTrue(first.Tiles |> List.exists (fun tile -> tile.Kind = (VillageArt.StonePaving)))
 
     [<TestMethod>]
+    member _.PauseHelpOpensFromPlayingAndRestoresSimulationControl () =
+        let original = { Paused = false; Speed = TwoX }
+        let state = { MenuState.create original true with Page = Playing }
+
+        let helpState, pausedControl = MenuState.enterPauseHelp original state
+        Assert.AreEqual<MenuPage>(Controls, helpState.Page)
+        Assert.AreEqual<MenuPage>(Playing, helpState.ReturnPage)
+        Assert.IsTrue(pausedControl.Paused)
+        Assert.AreEqual<SimulationSpeed>(TwoX, pausedControl.Speed)
+
+        let backState, restoredControl = MenuState.exitPauseHelp original helpState
+        Assert.AreEqual<MenuPage>(Playing, backState.Page)
+        Assert.IsFalse(restoredControl.Paused)
+        Assert.AreEqual<SimulationControl>(original, restoredControl)
+
+    [<TestMethod>]
     member _.CornerStatusShowsDayMoneyAndEnergyFromRealData () =
         let world = Sim.initialWorldN 42UL 0
         let lines = M5Interaction.cornerStatusLines world