[Bug Report] XPath scraper is missing string array support

[feederbox826]

Describe the bug
XPath scrapers can't return URLs in array format

To Reproduce
Steps to reproduce the behavior:

• Try to scrape with POC fapello scrapers
• when using stringarr

scrapePerformerURL: input: scrapePerformerURL Internal system error. Error <reflect.Set: value of type string is not assignable to type []string>
reflect.Set: value of type string is not assignable to type []string
[3][URLs] = https://NSFW
[0][URLs] = https://NSFW
[2][URLs] = https://NSFW
[1][URLs] = https://NSFW

• when using objarr

key 'URLs': selector '': parse error: expr expression is nil

Expected behavior
xPath selector is taken as an un-merged array or nested support like with Tags is possible

Stash Version: (from Settings -> About):
v0.27.0

Additional context
Related to #4958
Blocking stashapp/CommunityScrapers#2042

[DogmaDragon]

Reproduced on c45ae06.