refactor: set 'treat as' on enter-sut instruction

[AirQuick]

This pull request adds treat as to some parameters (x:call[@function] and not-yet-implemented x:apply`) in the compiled stylesheet/query.

This treat as is not mandatory, because @as is handled when mode="test:generate-variable-declarations" generates the variable. So this change is for robustness and for balance between the other code branches in xsl:choose.

[commit-lint]

Code Refactoring

• set 'treat as' on enter-sut instruction (a843fc9)

Tests

• xslt: duplicate xspec-param-as.xspec as *_stylesheet.xspec (56db455)
• adapt xspec-param-as.xspec to XQuery (3f89a92)
• add multi-param scenario to function-param test (23c79bc)
• xslt: use mirror.xsl in xspec-param-as_stylesheet.xspec (f43783d)

Contributors

@AirQuick