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/SharedFunctionStub.ts

@@ -1,6 +1,6 @@
 import { ISharedFunction, ISharedFunctionBody, FunctionBodyType } from '@/application/Parser/Script/Compiler/Function/ISharedFunction';
 import { IReadOnlyFunctionParameterCollection } from '@/application/Parser/Script/Compiler/Function/Parameter/IFunctionParameterCollection';
-import { IFunctionCall } from '@/application/Parser/Script/Compiler/Function/Call/IFunctionCall';
+import { FunctionCall } from '@/application/Parser/Script/Compiler/Function/Call/FunctionCall';
 import { FunctionParameterCollectionStub } from './FunctionParameterCollectionStub';
 import { FunctionCallStub } from './FunctionCallStub';
 
@@ -16,7 +16,7 @@ export class SharedFunctionStub implements ISharedFunction {
 
   private bodyType: FunctionBodyType = FunctionBodyType.Code;
 
-  private calls: IFunctionCall[] = [new FunctionCallStub()];
+  private calls: FunctionCall[] = [new FunctionCallStub()];
 
   constructor(type: FunctionBodyType) {
     this.bodyType = type;
@@ -53,7 +53,11 @@ export class SharedFunctionStub implements ISharedFunction {
     return this;
   }
 
-  public withCalls(...calls: readonly IFunctionCall[]) {
+  public withSomeCalls() {
+    return this.withCalls(new FunctionCallStub(), new FunctionCallStub());
+  }
+
+  public withCalls(...calls: readonly FunctionCall[]) {
     this.calls = [...calls];
     return this;
   }