[BUG] doc-available must work in a predicate

[line-o]

Describe the bug

doc-available cannot be used in a predicate.

('/db/a', '/db/b')[doc-available(.)]

yields

exerr:ERROR XPTY0004: The actual cardinality for parameter 1 does not match the cardinality declared in the function's signature: doc-available($document-uri as xs:string?) xs:boolean. Expected cardinality: zero or one, got 2. [at line 1, column 20, source: String/-2946985203662395848]

Expected behavior

In the above case the expected return value is an empty sequence as both path very likely point to a non XML document.

To Reproduce

xquery version "3.1";

module namespace t="http://exist-db.org/xquery/test";

declare namespace test="http://exist-db.org/xquery/xqsuite";

declare
    %test:setUp
function t:setup() {
    xmldb:create-collection("/db", "test"),
    xmldb:store("/db/test", "doc.xml", <root />),
    xmldb:store("/db/test", "bin",  "...")
};

declare
    %test:tearDown
function t:tearDown() {
    xmldb:remove("/db/test")
};

declare
    %test:assertEquals("/db/test/doc.xml")
function t:doc-available-in-predicate() {
    uri-collection("/db/test")[doc-available(.)]
};

declare
    %test:assertEquals("/db/test/bin")
function t:util-binary-doc-available-in-predicate() {
    uri-collection("/db/test")[util:binary-doc-available(.)]
};

On exist-6.2.0 only the second test passes.

Context (please always complete the following information)

Build: eXist-6.3.0-SNAPSHOT (b55849d)
Java: 1.8.0_362 (Azul Systems, Inc.)
OS: Mac OS X 14.3 (aarch64)

Additional context

• How is eXist-db installed? built from source
• Any custom changes in e.g. conf.xml? none