Change -Suffix parameter in Create-Clip.ps1 from optional empty string to required non-empty string with default value "-Clip", removing the hardcoded "-Clip" prefix from target name derivation so suffix is inserted directly before extension (e.g. default behavior unchanged: P01.mp4 -> P01-Clip.mp4, but custom -Suffix "-Shot-1" now makes P01.mp4 -> P01-Shot-1.mp4 instead of P01-Clip-Shot-1.mp4), add ValidateNotNullOrEmpty attribute, update documentation to reflect new default and behavior, and add installation

Create-Scenes.cmd

@@ -0,0 +1,2 @@
+@echo off
+pwsh.exe -NoProfile -ExecutionPolicy Bypass -File "%~dp0Create-Scenes.ps1" %*