[bugfix] 2643 bug search for account url doesnt always work when redirected (#2673)

* update activity library so dereferencer returns full response and checks *final* link to allow for redirects

* temporarily add bodged fixed library

* remove unused code

* update getAccountFeatured() to use dereferenceCollectionPage()

* make sure to release map

* perform a 2nd decode to ensure reader is empty after primary decode

* add comment explaining choice of using Decode() instead of Unmarshal()

* update embedded activity library to latest matching https://github.com/superseriousbusiness/activity/pull/21

* add checks to look for changed URI and re-check database if redirected

* update max iteration count to 512, add checks during dereferenceAncestors() for indirect URLs

* remove doubled-up code

* fix use of status instead of current

* use URIs for checking equality for security

* use the latest known URI for boost_of_uri in case original was an indirect

* add dereferenceCollection() function for dereferenceAccountFeatured()

* pull in latest github.com/superseriousbusiness/activity version (and remove the bodge!!)

* fix typo in code comments

* update decodeType() to accept a readcloser and handle body closing

* switch to checking using BoostOfID and add note why not using BoostOfURI

* ensure InReplyTo gets unset when deleting status parent in case currently stubbed

* add tests for Collection and CollectionPage iterators

internal/ap/interfaces.go

@@ -300,6 +300,15 @@ type ReplyToable interface {
 	WithInReplyTo
 }
 
+// CollectionIterator represents the minimum interface for interacting with a
+// wrapped Collection or OrderedCollection in order to access next / prev items.
+type CollectionIterator interface {
+	vocab.Type
+
+	NextItem() TypeOrIRI
+	PrevItem() TypeOrIRI
+}
+
 // CollectionPageIterator represents the minimum interface for interacting with a wrapped
 // CollectionPage or OrderedCollectionPage in order to access both next / prev pages and items.
 type CollectionPageIterator interface {