Fix compiler bug with nested optional arguments

This commit fixes compiler bug where it fails when optional values are
compiled into absent values in nested calls.

- Throw exception with more context for easier future debugging.
- Add better validation of argument values for nested calls.
- Refactor `FunctionCallCompiler` for better clarity and modularize it
  to make it more maintainable and testable.
- Refactor related interface to not have `I` prefix, and
  function/variable names for better clarity.

Context:

Discovered this issue while attempting to call
`RunInlineCodeAsTrustedInstaller` which in turn invokes `RunPowerShell`
for issue #246. This led to the realization that despite parameters
flagged as optional, the nested argument compilation didn't support
them.

tests/unit/shared/Stubs/FunctionCallStub.ts

@@ -1,7 +1,7 @@
-import { IFunctionCall } from '@/application/Parser/Script/Compiler/Function/Call/IFunctionCall';
+import { FunctionCall } from '@/application/Parser/Script/Compiler/Function/Call/FunctionCall';
 import { FunctionCallArgumentCollectionStub } from './FunctionCallArgumentCollectionStub';
 
-export class FunctionCallStub implements IFunctionCall {
+export class FunctionCallStub implements FunctionCall {
   public functionName = 'functionCallStub';
 
   public args = new FunctionCallArgumentCollectionStub();