[Core] Add Boolean Functions to expressions (AND, OR, NOT) (#22506)

* [Core] Add Boolean Functions to expressions (AND, OR, BOOL, NOT)

* [Core] Add `if` function to expressions to overcome ternary operator limitations

* [Core] Update expressions grammar to recognize relational operations as arguments

* [Core] The `if` function has been removed as no consensus was reached regarding its convenience or necessity. Its inclusion was considered potentially confusing or redundant.

* [Core] Make boolean cast based on Confusion threshold.

tests/src/App/Expression.cpp

@@ -5,6 +5,10 @@
 #include "App/ExpressionParser.h"
 #include "App/ExpressionTokenizer.h"
 
+// +------------------------------------------------+
+// | Note: For more expression related tests, see:  |
+// |       src/Mod/Spreadsheet/TestSpreadsheet.py   |
+// +------------------------------------------------+
 
 class Expression: public ::testing::Test
 {