NEON-27: check off all acceptance criteria; record PR screenshots

Before/after evidence: obstacle fades to ~25% alpha when occluding the
player; restores on clear. All three ACs satisfied.

docs/plans/NEON-27-implementation-plan.md

@@ -32,9 +32,11 @@
 
 ## Acceptance criteria checklist
 
-- [ ] In a documented test setup, occlusion **no longer fully hides** the player in the common worst case (before/after screenshot or short clip note in PR).
-- [ ] Policy is **configurable or data-driven** enough to iterate without rewriting core follow logic (`OcclusionPolicy` resource swappable in inspector; `fade_alpha`, `occluder_group`, and `occluder_collision_mask` are exported).
-- [ ] Risk called out in module doc: occlusion hiding telegraphs — link to **readability checklist** or gate note for prototype demo.
+- [x] In a documented test setup, occlusion **no longer fully hides** the player in the common worst case (before/after screenshot or short clip note in PR).
+  - **Before:** obstacle fully opaque, player visible only when clear of the geometry.
+  - **After:** obstacle fades to ~25% alpha when between the camera and player; player silhouette and slot indicator remain readable. Screenshots: `assets/Screenshot_20260408_234113-*.png` (faded), `assets/Screenshot_20260408_234125-*.png` (restored).
+- [x] Policy is **configurable or data-driven** enough to iterate without rewriting core follow logic (`OcclusionPolicy` resource swappable in inspector; `fade_alpha`, `occluder_group`, and `occluder_collision_mask` are exported).
+- [x] Risk called out in module doc: occlusion hiding telegraphs — link to **readability checklist** or gate note for prototype demo.
 
 ## Technical approach