feat: add initial People Playground mod development kit

extracted_wiki_content/internalReference/bellclip.txt

@@ -0,0 +1,24 @@
+URL: https://wiki.studiominus.nl/internalReference/BellClip.html
+Title: People Playground Modding - BellClip
+==================================================
+
+public class BellClip
+[System.Serializable]
+Represents a bell's note
+Fields
+public string Name
+Codename
+
+public PianoKey Key
+The PianoKey that this bell plays
+
+public int Octave
+The octave at which the note is played
+
+public AudioClip Clip
+[Space]
+The actual clip that is played
+
+Methods
+public string GetDisplayName(bool shorten = false)
+Build the display name