Document Get-VideoSubtitles.ps1 in README.md, index.md and SKILL.md, describing subtitle extraction and -List behavior, supported text and Blu-ray PGS formats, unsupported DVD and DVB bitmap tracks, and replacement of same-named output files in the current directory

Get-VideoSubtitles.cmd

@@ -0,0 +1,2 @@
+@echo off
+pwsh.exe -NoProfile -ExecutionPolicy Bypass -File "%~dp0Get-VideoSubtitles.ps1" %*