PowerRename Feature Idea: Simple Script per Folder

### Description of the new feature / enhancement

I use power rename a lot (thank you to the creative team behind this!) and would love to have the ability to save my recent renaming regex and substitution to a simple script file in a folder. This way, I could just double-click on the script in that folder to quickly run the rename again.

This is very helpful for my use cases, where I regularly download statements from various merchants or banks and then save them in the appropriate folder. But then I have to rename them manually from something like "Statement-013126-xxx9925.pdf" into something cleaner like "Statement 2026-01-31.pdf". Each bank or invoice formats differently, so having the saved "rename" script in that folder would reduce me having to recreate the regex each time I need to rename; and certainly would be faster than manually fumbling with F2 in explorer and re-arranging MMDDYY every time.

The script could be a simple JSON with regex match and substitute fields, just like what the UI shows. I would even be a happy camper if clicking the script brought up PowerRename with the regex and substitute fields filled in and then I could verify and apply manually. Though, an "AutoApply" power option in the script would be great too!

### Scenario when this would be used?

As described above, I frequently get invoices, bank statements, etc, that I organize into folders. Each statement comes in a different naming format unique to that bank and corresponding folder, so having the known regex/substitution script saved would bring me to the next level of super power-user! I'm excited just thinking about it!

### Supporting information

_No response_

Start by locating the PowerRename implementation and its existing UI flow for regex and substitution fields. Define how a folder script would be discovered, represented as JSON, opened, and optionally auto-applied. Done means a saved script can repopulate PowerRename reliably, with verification through the relevant tests or manual desktop scenarios.

Written by the indexing model from the issue text.