feat: web dashboard and playground work

The NexusDashboard-parity dashboard (dDashboardServer) and everything built on it on the experimental branch:
accounts, characters, properties and moderation tools, permissions shared with in-game slash commands, economy
reports, World 3D and property 3D views with client scenery, scheduled events (features, vanity changes, live
events, announcements, restarts), vanity files and events, the CDClient browser, the message inspector with saved
captures, chat filter tools, community challenges, live ops, the AI moderator helper, and the server-side changes
they need.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

dCommon/NiColor.h

@@ -0,0 +1,34 @@
+#ifndef NICOLOR_H
+#define NICOLOR_H
+
+struct NiColor {
+	float m_Red;
+	float m_Green;
+	float m_Blue;
+
+	constexpr NiColor(float red, float green, float blue) : m_Red(red), m_Green(green), m_Blue(blue) {}
+	constexpr NiColor() : NiColor(0.0f, 0.0f, 0.0f) {}
+
+	/* reduce RGB files to grayscale, with or without alpha
+	 * using the equation given in Poynton's ColorFAQ at
+	 * <http://www.inforamp.net/~poynton/> // dead link
+	 * Copyright (c) 1998-01-04 Charles Poynton poynton at inforamp.net
+	 *
+	 *     Y = 0.212671 * R + 0.715160 * G + 0.072169 * B
+	 *
+	 *  We approximate this with
+	 *
+	 *     Y = 0.21268 * R    + 0.7151 * G    + 0.07217 * B
+	 *
+	 *  which can be expressed with integers as
+	 *
+	 *     Y = (6969 * R + 23434 * G + 2365 * B)/32768
+	 *
+	 *  The calculation is to be done in a linear colorspace.
+	 *
+	 *  Other integer coefficents can be used via png_set_rgb_to_gray().
+	 */
+	float ToXYZ() const { return (m_Red * 0.212671f) + (m_Green * 0.71516f) + (m_Blue * 0.072169f); };
+};
+
+#endif // NICOLOR_H