Step 516: add signature visual identity primitives

editor/src/SignatureVisualIdentity.h

@@ -0,0 +1,81 @@
+#pragma once
+// Step 516: Signature Visual Identity Pack
+// Encodes black-surface gradient treatment, blade-edge accents, and
+// electric-blue logic link styling.
+
+#include <string>
+#include <vector>
+#include <algorithm>
+
+struct GradientStop {
+    float t = 0.0f;
+    float r = 0.0f;
+    float g = 0.0f;
+    float b = 0.0f;
+    float a = 1.0f;
+};
+
+struct EdgeAccent {
+    std::string edge; // left/right/top/bottom
+    float thickness = 1.0f;
+    float intensity = 0.0f;
+    bool active = false;
+};
+
+struct LogicLinkStyle {
+    float width = 1.0f;
+    float glow = 0.0f;
+    float r = 0.15f;
+    float g = 0.56f;
+    float b = 0.95f;
+    float alpha = 1.0f;
+};
+
+class SignatureVisualIdentity {
+public:
+    static std::vector<GradientStop> blackSurfaceGradient(bool elevated) {
+        if (elevated) {
+            return {
+                {0.0f, 0.02f, 0.02f, 0.02f, 1.0f},
+                {0.45f, 0.08f, 0.08f, 0.08f, 1.0f},
+                {1.0f, 0.14f, 0.14f, 0.14f, 1.0f}
+            };
+        }
+        return {
+            {0.0f, 0.01f, 0.01f, 0.01f, 1.0f},
+            {0.60f, 0.05f, 0.05f, 0.05f, 1.0f},
+            {1.0f, 0.09f, 0.09f, 0.09f, 1.0f}
+        };
+    }
+
+    static EdgeAccent bladeEdge(const std::string& edge, bool active, float emphasis) {
+        EdgeAccent a;
+        a.edge = edge;
+        a.active = active;
+        a.thickness = active ? 2.0f : 1.0f;
+        a.intensity = active ? std::max(0.2f, std::min(1.0f, emphasis)) : 0.12f;
+        return a;
+    }
+
+    static LogicLinkStyle electricBlueLink(bool highlighted, float distanceNorm) {
+        LogicLinkStyle s;
+        s.width = highlighted ? 2.4f : 1.4f;
+        s.glow = highlighted ? 0.80f : 0.35f;
+        float fade = std::max(0.35f, 1.0f - std::max(0.0f, std::min(1.0f, distanceNorm)) * 0.45f);
+        s.alpha = fade;
+        return s;
+    }
+
+    static bool isElectricBlue(const LogicLinkStyle& s) {
+        return s.b > s.r && s.b > s.g && s.g > s.r;
+    }
+
+    static float revealDurationMs(bool reducedMotion) {
+        return reducedMotion ? 80.0f : 220.0f;
+    }
+
+    static float staggerDelayMs(int index, bool reducedMotion) {
+        if (reducedMotion) return 0.0f;
+        return std::max(0, index) * 24.0f;
+    }
+};