fix(desktop): 键位页键名列统一宽度不叠印

Controls 页按键名列独立成列（ControlsKeyX/KeyWidth=120/ActionX），controlRowRects 纯函数返回键名与动作矩形，回归测试断言逐行矩形不相交、全部行键名列 x/宽度一致、列宽容纳最长键名 F1/F2/F3；面板上移至 ControlsPanelY 保证 14 行键位加页脚完整落入视口。

3 files changed, 47 insertions, 3 deletions

diff --git a/src/LivingVillage.Desktop.Tests/PrototypeTests.fs b/src/LivingVillage.Desktop.Tests/PrototypeTests.fs
index c85287f..77d2530 100644
--- a/src/LivingVillage.Desktop.Tests/PrototypeTests.fs
+++ b/src/LivingVillage.Desktop.Tests/PrototypeTests.fs
@@ -219,6 +219,29 @@ type PrototypeTests () =
         Assert.AreEqual<SimulationControl>(original, restoredControl)
 
     [<TestMethod>]
+    member _.ControlsPageKeyColumnIsUniformAndNeverOverprintsActions () =
+        let layout = TitleScreen.layout 1280 720
+        let rows = MenuState.controlRows
+
+        // Every row: key-name rectangle and action rectangle must be disjoint.
+        for rowIndex in 0 .. rows.Length - 1 do
+            let keyRect, actionRect = TitleScreen.controlRowRects layout rowIndex
+            Assert.IsTrue(TitleScreen.rectsDisjoint keyRect actionRect, sprintf "row %d key overlaps action" rowIndex)
+
+        // The key column is uniform: every row shares the same x and width.
+        let keyRects = [ 0 .. rows.Length - 1 ] |> List.map (fun index -> TitleScreen.controlRowRects layout index |> fst)
+        Assert.AreEqual<int>(1, keyRects |> List.map (fun rect -> rect.X) |> List.distinct |> List.length)
+        Assert.AreEqual<int>(1, keyRects |> List.map (fun rect -> rect.Width) |> List.distinct |> List.length)
+
+        // The key column fits the longest key name (latin glyph: 6px * scale 2 per char).
+        let longestKey = rows |> List.maxBy (fun row -> row.Keys.Length)
+        Assert.IsTrue(layout.ControlsKeyWidth >= longestKey.Keys.Length * 12, sprintf "key width %d too small for %s" layout.ControlsKeyWidth longestKey.Keys)
+
+        // The controls panel holds every row plus the footer inside the viewport.
+        let panelBottom = layout.ControlsPanelY + 60 + rows.Length * layout.ControlsRowHeight + 48
+        Assert.IsTrue(panelBottom <= 720, sprintf "controls panel bottom %d overflows" panelBottom)
+
+    [<TestMethod>]
     member _.CornerStatusShowsDayMoneyAndEnergyFromRealData () =
         let world = Sim.initialWorldN 42UL 0
         let lines = M5Interaction.cornerStatusLines world
diff --git a/src/LivingVillage.Desktop/Game.fs b/src/LivingVillage.Desktop/Game.fs
index 7337129..25b8c48 100644
--- a/src/LivingVillage.Desktop/Game.fs
+++ b/src/LivingVillage.Desktop/Game.fs
@@ -547,6 +547,8 @@ type LivingVillageGame() as this =
             | LoadError -> 4
             | Playing -> 0
         let rowHeight = if menu.Page = Controls then 25 else layout.MenuLineHeight
+        let panelY =
+            if menu.Page = Controls then layout.ControlsPanelY else layout.PanelY
         let panelHeight =
             min (height - panelY - 16)
                 (max layout.PanelHeight (120 + contentRows * rowHeight + 48))
@@ -622,7 +624,9 @@ type LivingVillageGame() as this =
             drawText innerX (layout.HeadingY) mutedColor (ChineseText.menuHeading ControlsHeading)
             MenuState.controlRows
             |> List.iteri (fun index row ->
-                drawText innerX (contentY + index * 25) textColor (sprintf "%s %s" row.Keys row.Action))
+                let keyRect, actionRect = TitleScreen.controlRowRects layout index
+                PixelText.draw spriteBatch pixel cjkAtlas keyRect.X keyRect.Y textScale textColor row.Keys
+                PixelText.draw spriteBatch pixel cjkAtlas actionRect.X actionRect.Y textScale textColor row.Action)
             drawText innerX (panelY + panelHeight - 40) mutedColor "ESC 返回"
         | LoadError ->
             drawText innerX (layout.HeadingY) (Color(240, 130, 120)) "读取失败"
diff --git a/src/LivingVillage.Desktop/TitleScreen.fs b/src/LivingVillage.Desktop/TitleScreen.fs
index 00cf5b8..7ec46d2 100644
--- a/src/LivingVillage.Desktop/TitleScreen.fs
+++ b/src/LivingVillage.Desktop/TitleScreen.fs
@@ -29,7 +29,12 @@ module TitleScreen =
           FirstItemY: int
           CursorX: int
           CursorWidth: int
-          TextX: int }
+          TextX: int
+          ControlsPanelY: int
+          ControlsRowHeight: int
+          ControlsKeyX: int
+          ControlsKeyWidth: int
+          ControlsActionX: int }
 
     type TextRect =
         { X: int
@@ -43,6 +48,13 @@ module TitleScreen =
         || a.Y + a.Height <= b.Y
         || b.Y + b.Height <= a.Y
 
+    /// Key-name and action rectangles for one controls-page row. The key column has a
+    /// fixed width shared by every row, so all action texts start on the same x.
+    let controlRowRects (layout: TitleLayout) (rowIndex: int) : TextRect * TextRect =
+        let y = layout.FirstItemY + rowIndex * layout.ControlsRowHeight
+        { X = layout.ControlsKeyX; Y = y; Width = layout.ControlsKeyWidth; Height = 16 },
+        { X = layout.ControlsActionX; Y = y; Width = layout.PanelX + layout.PanelWidth - layout.ControlsActionX - 24; Height = 16 }
+
     /// Cursor and label rectangles for one menu row. The cursor is drawn in its own
     /// column; the label always starts to the right of it, so they can never overprint.
     let selectionRects (layout: TitleLayout) (rowIndex: int) : TextRect * TextRect =
@@ -111,4 +123,9 @@ module TitleScreen =
           FirstItemY = height / 2 - 64 + 60
           CursorX = (width - panelWidth) / 2 + 24
           CursorWidth = 20
-          TextX = (width - panelWidth) / 2 + 24 + 20 + 12 }
+          TextX = (width - panelWidth) / 2 + 24 + 20 + 12
+          ControlsPanelY = max 16 (height - 480)
+          ControlsRowHeight = 25
+          ControlsKeyX = (width - panelWidth) / 2 + 24
+          ControlsKeyWidth = 120
+          ControlsActionX = (width - panelWidth) / 2 + 24 + 120 + 12 }