p75: HUD 顶部条去整宽深色带（改紧凑半透明药丸）

HudLayout：BarTop/BarBottom alpha=0，新增 pillHairline 1px 发丝线与 pillHeight；DrawHudBar 不再铺整条底色与整宽 accent，改画每段半透明药丸+发丝线，图标+数值并排、右侧留白充足。布局/语义/快捷键不变，HUD 结构仅视觉层次。新增 P75HudStripTests（4 例）；LV_P43_SHOT 同机位昼/夜证据 + analyze-p75（顶部条近黑 2.6% vs 整宽带 100%、无实心黑块、亮字仍在，verdict=PASS）。Desktop 354/354、Kernel 120/120、digest 与 p70 一致。

1 files changed, 59 insertions, 0 deletions

diff --git a/src/LivingVillage.Desktop.Tests/P75HudStripTests.fs b/src/LivingVillage.Desktop.Tests/P75HudStripTests.fs
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+++ b/src/LivingVillage.Desktop.Tests/P75HudStripTests.fs
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+namespace LivingVillage.Desktop.Tests
+
+open Microsoft.VisualStudio.TestTools.UnitTesting
+open LivingVillage.Desktop
+open LivingVillage.Kernel
+open LivingVillage.Kernel.Sim
+
+/// P75 回归：HUD 顶部条改为紧凑半透明药丸（去整宽深色带），信息不遮挡、文字可读。
+[<TestClass>]
+type P75HudStripTests () =
+
+    let world = Sim.initialWorldN 42UL 4
+    let control = SimulationControl.initial
+    let placed = HudLayout.layout (HudLayout.segments world control)
+
+    [<TestMethod>]
+    member _.TopBandIsRemovedForDayAndNight () =
+        for mode in [ Day; Night ] do
+            let palette = HudLayout.palette mode
+            Assert.AreEqual<byte>(0uy, palette.BarTop.A)
+            Assert.AreEqual<byte>(0uy, palette.BarBottom.A)
+        Assert.AreEqual<byte>(0uy, HudLayout.bandAlpha)
+
+    [<TestMethod>]
+    member _.PillsAreCompactInsideTheStrip () =
+        Assert.IsTrue(HudLayout.pillHeight < HudLayout.barHeight, "药丸须比窄条矮，留出上下留白")
+        for (x, width, _) in placed do
+            let pill = HudLayout.segmentBackdrop x width
+            Assert.IsTrue(pill.Y >= 0 && pill.Y + pill.Height <= HudLayout.barHeight, "药丸须在窄条内")
+            let hair = HudLayout.pillHairline x width
+            Assert.IsTrue(hair.Height = 1, "发丝线为 1px")
+            Assert.IsTrue(hair.X >= pill.X && hair.X + hair.Width <= pill.X + pill.Width, "发丝线须在药丸内")
+            Assert.AreEqual<int>(max 1 (pill.Width - 2), hair.Width)
+
+    [<TestMethod>]
+    member _.StripLeavesWhitespaceAndDoesNotOverlapDateCard () =
+        Assert.IsTrue(placed.Length > 0)
+        let firstX = placed |> List.head |> fun (x, _, _) -> x
+        Assert.AreEqual<int>(HudLayout.paddingX, firstX)
+        let lastEnd = placed |> List.last |> fun (x, width, _) -> x + width
+        // 药丸总跨度远小于通栏宽度，右侧留白充足（不再铺满整宽）。
+        Assert.IsTrue(lastEnd < 1280 / 2, sprintf "HUD 只占左半，右侧留白；lastEnd=%d" lastEnd)
+        let reading = HudLayout.calendarReading world.Tick
+        let cal = HudLayout.calendarCardRect 1280 reading
+        Assert.IsTrue(cal.Y >= HudLayout.barHeight + HudLayout.accentHeight, "日历卡不压顶部条")
+
+    [<TestMethod>]
+    member _.TextStaysReadableOnTranslucentPills () =
+        for mode in [ Day; Night ] do
+            let palette = HudLayout.palette mode
+            Assert.IsTrue(palette.SegmentBackdrop.A > 0uy && palette.SegmentBackdrop.A < 255uy, "药丸半透明")
+            let valueLuma = int palette.Value.R + int palette.Value.G + int palette.Value.B
+            let outlineLuma = int palette.Outline.R + int palette.Outline.G + int palette.Outline.B
+            Assert.IsTrue(valueLuma > 600, "数值色须够亮")
+            Assert.IsTrue(valueLuma > outlineLuma + 400, "亮字 vs 深描边对比须足够")
+            // 图标与数值并排：文本起始在图标右侧。
+            for (x, _, segment) in placed do
+                Assert.AreEqual<int>(x + HudLayout.iconWidth + HudLayout.iconGap, HudLayout.textOrigin x)
+                Assert.IsFalse(System.String.IsNullOrEmpty segment.Value)