Refactor to unify scripts/categories as Executable

This commit consolidates scripts and categories under a unified
'Executable' concept. This simplifies the architecture and improves code
readability.

- Introduce subfolders within `src/domain` to segregate domain elements.
- Update class and interface names by removing the 'I' prefix in
  alignment with new coding standards.
- Replace 'Node' with 'Executable' to clarify usage; reserve 'Node'
  exclusively for the UI's tree component.

src/application/Parser/Executable/Script/Compiler/Function/Call/FunctionCall.ts

@@ -0,0 +1,6 @@
+import type { IReadOnlyFunctionCallArgumentCollection } from './Argument/IFunctionCallArgumentCollection';
+
+export interface FunctionCall {
+  readonly functionName: string;
+  readonly args: IReadOnlyFunctionCallArgumentCollection;
+}