Hazard: destructible cover — carve-able rocks that genuinely block until broken

Phase 1.5 long-term #8, the LAST 1.5 item (design review wf_e14dd739-069:
both HIGHs + the distinct MEDs verified before the session limit ate the
duplicate verifiers; unverified leftovers reasoned-closed in the spec).

Cover = a BlightClutter ghost (Variant 4) with a baked Environment-layer
BoxCollider: the runtime ghost's collider joins BuildPhysicsWorld ->
blocks the player CC and the enemy sweep while alive, and the gap opens
the instant the entity dies. Both hit paths already break it (the
clutter chassis); 8 hits to carve.

Review folds:
- HIGH: the 07-07 anti-stuck nudge would phase enemies THROUGH cover
  after ~1.5s (it exists to prevent room soft-locks). The nudge is now
  COVER-AWARE: a SphereCast identifies the blocker; a live BlightClutter
  ghost suppresses the phase (no soft-lock possible - the blocker is
  destructible); static-geometry wedges still nudge.
- HIGH: yield==durability made tanky cover an economy faucet. Deposit
  is DECOUPLED from the decrement at both hit sites: ScrapPerHit=0 =
  breaks in Remaining hits, yields NOTHING; fractional POSITIVE yields
  still credit >=1 (the B1 immortal-sink test pinned this - zero means
  zero, positive floors to 1).
- MEDs: HitRadius 1.2 (visual core, not a shot-eating disc), NO cover
  in Boss rooms (no boss depenetration backstop), scatter keep-out >=7u
  from the room origin (player landing + portal), Variant=4 explicit
  (the clutter block's explosive reroll cannot leak).
- Old static layer removed: 8 WorldColliders_RoomCover colliders
  (subscene) + the RoomCover_Visuals root (Game.unity).

Verified live: 3 cover ghosts spawned with SOLID baked colliders;
BLOCK - NudgeUntilTick stayed 0 across 3.5s of forced zero-progress
(old code arms at 1.5s); DEPENETRATE - an enemy shoved inside a live
rock exited to 1.7u (backstop holds against ghost colliders); CARVE -
the rock died to the real sweep and the spot probed OPEN. 470/470
EditMode; console clean.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

Assets/_Project/Scripts/Authoring/Economy/BlightClutterAuthoring.cs

@@ -16,8 +16,8 @@ namespace ProjectM.Authoring
         [Tooltip("Hit-points before the clutter shatters.")]
         [Min(1)] public int Remaining = 2; // one-hit pop: both hit paths decrement by max(1,(int)ScrapPerHit)
 
-        [Tooltip("Scrap (Biomass) yielded per projectile hit — the 'minor scrap' trickle.")]
-        [Min(1f)] public float ScrapPerHit = 2f;
+        [Tooltip("Scrap (Biomass) yielded per hit. 0 = DESTRUCTIBLE COVER semantics: breaks in Remaining hits, yields nothing (deposit is decoupled from the decrement at both hit sites).")]
+        [Min(0f)] public float ScrapPerHit = 2f;
 
         [Tooltip("Hit radius (world units) for the clear sweep.")]
         [Min(0f)] public float HitRadius = 1.0f;

Assets/_Project/Scripts/Authoring/Economy/CoverFieldSpawnerAuthoring.cs

@@ -0,0 +1,35 @@
+using ProjectM.Simulation;
+using Unity.Entities;
+using UnityEngine;
+
+namespace ProjectM.Authoring
+{
+    /// <summary>
+    /// Authoring for the baked <see cref="CoverFieldSpawner"/> singleton (mirrors ClutterFieldSpawnerAuthoring).
+    /// Place once in the gameplay subscene and assign the CoverRock ghost prefab; RoomFieldSystem scatters
+    /// destructible cover per room (never in Boss rooms) with an origin keep-out. Carries no transform.
+    /// </summary>
+    public class CoverFieldSpawnerAuthoring : MonoBehaviour
+    {
+        [Tooltip("CoverRock ghost prefab: BlightClutterAuthoring (ScrapPerHit=0, Variant=4) + an Environment-layer collider + a GhostAuthoringComponent (ownerless, interpolated).")]
+        public GameObject CoverPrefab;
+
+        [Tooltip("Cover rocks per room (Boss rooms get none).")]
+        [Min(0)] public int Count = 3;
+
+        private class CoverFieldSpawnerBaker : Baker<CoverFieldSpawnerAuthoring>
+        {
+            public override void Bake(CoverFieldSpawnerAuthoring authoring)
+            {
+                var entity = GetEntity(authoring, TransformUsageFlags.None);
+                AddComponent(entity, new CoverFieldSpawner
+                {
+                    Prefab = authoring.CoverPrefab != null
+                        ? GetEntity(authoring.CoverPrefab, TransformUsageFlags.Dynamic)
+                        : Entity.Null,
+                    Count = authoring.Count,
+                });
+            }
+        }
+    }
+}

Assets/_Project/Scripts/Authoring/Economy/CoverFieldSpawnerAuthoring.cs.meta

@@ -0,0 +1,2 @@
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