[FIR][LightTree] Generate and fix missing tests

Add TYPE_PARAMETERS_LIST positioning
Use whole branch as source in when branches

compiler/testData/diagnostics/tests/annotations/kt1860-negative.fir.kt

@@ -4,7 +4,7 @@ fun foo(@<!UNRESOLVED_REFERENCE!>varargs<!> f : Int) {}
 var bar : Int = 1
   set(@<!UNRESOLVED_REFERENCE!>varargs<!> v) {}
 
-val x : (Int) -> Int = {@<!UNRESOLVED_REFERENCE!>varargs<!> x <!SYNTAX!>: Int -> x<!>}
+val x : (Int) -> Int = <!INITIALIZER_TYPE_MISMATCH{LT}!>{@<!UNRESOLVED_REFERENCE!>varargs<!> x <!SYNTAX!>: Int -> x<!>}<!>
 
 class Hello(@<!UNRESOLVED_REFERENCE!>varargs<!> args: Any) {
 }

compiler/testData/diagnostics/tests/annotations/kt1860-positive.fir.kt

@@ -8,7 +8,7 @@ fun foo(@test f : Int) {}
 var bar : Int = 1
     set(@test v) {}
 
-val x : (Int) -> Int = {@test x <!SYNTAX!>: Int -> x<!>} // todo fix parser annotation on lambda parameter
+val x : (Int) -> Int = <!INITIALIZER_TYPE_MISMATCH{LT}!>{@test x <!SYNTAX!>: Int -> x<!>}<!> // todo fix parser annotation on lambda parameter
 
 class Hello(@test args: Any) {
 }