Combat: MC-4 combo-chain melee as the primary verb (DR-030)

Melee combo (left-click / pad-West) becomes the player's primary verb; the ranged projectile is demoted to right-click / pad-left-trigger. Predicted, owner-replicated combo Step (path-dependent -> [GhostField] anchor + absolute-write idempotency, NOT derived like the dash), server-only cleave mirroring ProjectileDamageSystem (SourceTick-stamped DamageEvent + KnockbackState), dash-cancellable movement-commit, 9 live TuningConfig knobs, and swing juice scaling with the combo step. The MC-6 archetype byte is deferred (the melee is its own verb). See DR-030.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Assets/_Project/Scripts/Simulation/Combat/MeleeConeMath.cs

@@ -0,0 +1,39 @@
+using Unity.Mathematics;
+
+namespace ProjectM.Simulation
+{
+    /// <summary>
+    /// Pure, deterministic cone hit-test for the MC-4 melee cleave. Shares the EXACT range + bearing predicate with
+    /// <see cref="AutoTarget"/> (planar XZ distance gate + <c>dot(bearing, facing) &gt;= cos(halfAngle)</c>) but as a
+    /// per-candidate boolean, so the cleave can collect ALL enemies in the cone — <see cref="AutoTarget.Resolve"/> is a
+    /// single-winner reducer and cannot be reused for collect-all (MC-4 review REUSE-1). Burst-safe, allocation-free,
+    /// no wall-clock / no randomness; intended to run server-side inside the predicted <c>MeleeComboSystem</c>.
+    /// </summary>
+    public static class MeleeConeMath
+    {
+        /// <summary>
+        /// True iff <paramref name="targetPos"/> lies within <paramref name="range"/> (planar XZ) of
+        /// <paramref name="from"/> AND its bearing from <paramref name="from"/> is within the cone half-angle of
+        /// <paramref name="facingDir"/> (<paramref name="cosHalfAngle"/> = cos(halfAngle)). A coincident
+        /// (zero-distance) target is excluded (undefined bearing). <paramref name="facingDir"/> must be
+        /// caller-normalized; a zero-length facing or a non-positive range returns false.
+        /// </summary>
+        public static bool InCone(float3 from, float2 facingDir, float range, float cosHalfAngle, float3 targetPos)
+        {
+            if (range <= 0f || math.lengthsq(facingDir) < 1e-6f)
+                return false;
+
+            float3 offset = targetPos - from;
+            float2 planar = new float2(offset.x, offset.z);
+            float distSq = math.lengthsq(planar);
+
+            if (distSq < 1e-6f)
+                return false;                 // coincident -> undefined bearing
+            if (distSq > range * range)
+                return false;                 // out of range
+
+            float2 bearing = planar * math.rsqrt(distSq); // normalized planar bearing
+            return math.dot(bearing, facingDir) >= cosHalfAngle;
+        }
+    }
+}