🔦 Fix flashlight beam not tracking view pitch

The light was positioned once at toggle time and then handed to the engine
via SetParent + SetParentAttachmentMaintainOffset on the pawn's
`axis_of_intent` attachment. That attachment carries the body's yaw but not
the view pitch, so once parented the beam could only ever rotate
horizontally — looking up or down did nothing.

Drop the parenting and drive the light's transform ourselves every tick from
the pawn's live AbsOrigin and V_angle, which is how the plugin behaved before
0.1.1 replaced the per-tick teleport with a parented entity.

Also:
- OnTick no longer short-circuits on !AllowUseKey, which otherwise stopped
  the light updating for servers that only expose css_fl_toggle.
- ForwardDistance now offsets the light horizontally only. Applying it along
  the pitched forward vector put the light below ground when looking straight
  down (crouched eye height 46 minus 54).
- Sweep up the light when the pawn is dead; an un-parented entity no longer
  dies with its pawn.
- Remove the now-unused AttachmentName config key.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

Flashlight.Tests/FlashlightLogicTests.cs

@@ -70,6 +70,79 @@ public class FlashlightLogicTests
         Assert.Equal(0f, forward.Z, 3);
     }
 
+    [Fact]
+    public void ForwardFromAnglesDegrees_PitchDrivesVerticalComponent()
+    {
+        // Source angles are inverted on pitch: positive pitch looks down.
+        Assert.True(FlashlightLogic.ForwardFromAnglesDegrees(45f, 0f).Z < 0f);
+        Assert.True(FlashlightLogic.ForwardFromAnglesDegrees(-45f, 0f).Z > 0f);
+    }
+
+    [Fact]
+    public void HorizontalForwardFromYawDegrees_HasNoVerticalComponent()
+    {
+        foreach (var yaw in new[] { -180f, -90f, -45f, 0f, 45f, 90f, 180f })
+        {
+            Assert.Equal(0f, FlashlightLogic.HorizontalForwardFromYawDegrees(yaw).Z, 5);
+        }
+    }
+
+    [Fact]
+    public void CalculateLightTransform_AnglesCarryFullViewRotation()
+    {
+        var transform = FlashlightLogic.CalculateLightTransform(
+            pawnOrigin: new Vector3(0f, 0f, 0f),
+            pitch: -35f,
+            yaw: 90f,
+            roll: 12f,
+            eyeOffsetZ: 64f,
+            forwardDistance: 54f);
+
+        // Pitch must survive into the light's angles, otherwise the beam only tracks yaw.
+        Assert.Equal(-35f, transform.Angles.X, 3);
+        Assert.Equal(90f, transform.Angles.Y, 3);
+        Assert.Equal(12f, transform.Angles.Z, 3);
+    }
+
+    [Theory]
+    [InlineData(-89f)]
+    [InlineData(-45f)]
+    [InlineData(0f)]
+    [InlineData(45f)]
+    [InlineData(89f)]
+    public void CalculateLightTransform_PitchNeverMovesTheOrigin(float pitch)
+    {
+        var transform = FlashlightLogic.CalculateLightTransform(
+            new Vector3(0f, 0f, 0f),
+            pitch,
+            yaw: 0f,
+            roll: 0f,
+            eyeOffsetZ: 64f,
+            forwardDistance: 54f);
+
+        // The muzzle stays at eye height and eye-forward regardless of pitch, so
+        // looking up or down can never shove the light through the ceiling or floor.
+        Assert.Equal(54f, transform.Origin.X, 3);
+        Assert.Equal(0f, transform.Origin.Y, 3);
+        Assert.Equal(64f, transform.Origin.Z, 3);
+    }
+
+    [Fact]
+    public void CalculateLightTransform_YawDrivesHorizontalOffset()
+    {
+        var transform = FlashlightLogic.CalculateLightTransform(
+            new Vector3(10f, 20f, 30f),
+            pitch: 0f,
+            yaw: 90f,
+            roll: 0f,
+            eyeOffsetZ: 64f,
+            forwardDistance: 54f);
+
+        Assert.Equal(10f, transform.Origin.X, 3);
+        Assert.Equal(74f, transform.Origin.Y, 3);
+        Assert.Equal(94f, transform.Origin.Z, 3);
+    }
+
     [Fact]
     public void ShouldCreateAndDestroyLight_Policies()
     {
@@ -98,7 +171,6 @@ public class FlashlightLogicTests
             ForwardDistance = -10f,
             StandEyeOffsetZ = -1f,
             CrouchEyeOffsetZ = -1f,
-            AttachmentName = " ",
             LightCookie = ""
         };
 
@@ -118,7 +190,6 @@ public class FlashlightLogicTests
         Assert.Equal(0f, config.ForwardDistance);
         Assert.Equal(0f, config.StandEyeOffsetZ);
         Assert.Equal(0f, config.CrouchEyeOffsetZ);
-        Assert.Equal("axis_of_intent", config.AttachmentName);
         Assert.Equal("materials/effects/lightcookies/flashlight.vtex", config.LightCookie);
     }