Ship the 0.8.0 first-hour and campaign milestone

Add the campaign shell, pause-safe checkpoint resume, post-shift campaign
continue, confirmed campaign reset, difficulty presets, searchable Help,
content-matrix validation, recovery events, contextual dialogue, policy/debrief
context and eligible-event previews. Extend persistence with atomic separate
files and add campaign/checkpoint/tutorial smokes. Headless 247/247, Python
94/94, tutorial/campaign/session/scenario smokes green.

src/core/crowd_system.gd

@@ -65,3 +65,11 @@ func summary() -> Dictionary:
 		"attention": attention,
 		"panic": crowd_panic,
 	}
+
+func snapshot() -> Dictionary:
+	return summary()
+
+func restore(data: Dictionary) -> void:
+	mood = clampf(float(data.get("mood", 0.05)), 0.0, 1.0)
+	attention = clampf(float(data.get("attention", 0.0)), 0.0, 1.0)
+	crowd_panic = bool(data.get("panic", mood >= 0.75))