Improved instructions for new users adding scripts

[cv-on-hub]

This should be a PR for changes to www.finalelua.com/help/install/script except I can't find where the source Docs page is located.

The current install/script instructions are confusing, and the thoughtful inclusion of all JW/RGP options makes it more complex than it needs to be. Attached below a suggestion for a simpler version recommending RGP alone (Mac-specific). Look forward to Review from @Nick-Mazuk. I realise that adding single scripts is common, but setting aside a dedicated folder other than inside the actual Plug-ins folder, feels the most versatile and easily understandable option.

[Nick-Mazuk]

The plugin and script install docs are currently hard-coded into the docs repo. Here's the file for the script install docs.

https://github.com/finale-lua/jw-lua-scripts-docs/blob/main/src/routes/help/install/script.svelte

Here's the actual lines of code for the instructions. If you know HTML, you can write raw HTML here.

https://github.com/finale-lua/jw-lua-scripts-docs/blob/7557fd969eac523db776264730995a58b91e3e15/src/routes/help/install/script.svelte#L37-L87

Given that (almost) no one should install JW Lua anymore, I'd be fine removing the JW Lua specific verbiage. I'd caution against making this macOS only, though, because we do have many Windows users.

At some point I should improve how the docs are generated. Especially as more people are becoming active and I'm less so.

[cv-on-hub]

Here's my suggested re-wording. Should work for Mac/Win and any matching version of RGPLua. I've only changed wording in the Ordered List, leaving the boundary material alone.
script_cv.svelte.txt

[cv-on-hub]

This has been raised as PR#28 under jw-lua-scripts-docs at finale-lua/jw-lua-scripts-docs#28