Using iOS14.5,
My URL looks like this:  https://www.myexample.com/invitation?invitationCode=123456
Inside my apple-app-site-association file, which components is correct ?
(Please notice the tiny difference of /invitation vs. /invitation* vs. /invitation/ vs. /invitation/* inside the component)
A) ?
"components": [
    {   "/": "/invitation",
        "?": { "invitationCode": "??????" }
    }
]
or B) ?
"components": [
    {   "/": "/invitation*",
        "?": { "invitationCode": "??????" }
    }
]
or C) ?
"components": [
    {   "/": "/invitation/",
        "?": { "invitationCode": "??????" }
    }
]
or D) ?
"components": [
    {   "/": "/invitation/*",
        "?": { "invitationCode": "??????" }
    }
]
Or is it even something else ?
 
                        
Option D looks okay it means that, "Matches any URL whose path starts with /invitation/ and which has a query item with name 'invitationCode' and a value of exactly 6 characters". If you invitation code always be 6 characters it works otherwise you can remove query parameter value.
For more information you can check the Apple Documentation which is my reference.