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/Validation/ExecutableValidator.ts

@@ -0,0 +1,69 @@
+import { isString } from '@/TypeHelpers';
+import type { ExecutableData } from '@/application/collections/';
+import { type ExecutableErrorContext } from './ExecutableErrorContext';
+import { createExecutableContextErrorMessage, type ExecutableContextErrorMessageCreator } from './ExecutableErrorContextMessage';
+
+export interface ExecutableValidatorFactory {
+  (context: ExecutableErrorContext): ExecutableValidator;
+}
+
+export interface ExecutableValidator {
+  assertValidName(nameValue: string): void;
+  assertDefined(
+    data: ExecutableData | undefined,
+  ): asserts data is NonNullable<ExecutableData> & void;
+  assert(
+    validationPredicate: () => boolean,
+    errorMessage: string,
+  ): asserts validationPredicate is (() => true);
+  createContextualErrorMessage(errorMessage: string): string;
+}
+
+export const createExecutableDataValidator
+: ExecutableValidatorFactory = (context) => new ContextualExecutableValidator(context);
+
+export class ContextualExecutableValidator implements ExecutableValidator {
+  constructor(
+    private readonly context: ExecutableErrorContext,
+    private readonly createErrorMessage
+    : ExecutableContextErrorMessageCreator = createExecutableContextErrorMessage,
+  ) {
+
+  }
+
+  public assertValidName(nameValue: string): void {
+    this.assert(() => Boolean(nameValue), 'missing name');
+    this.assert(
+      () => isString(nameValue),
+      `Name (${JSON.stringify(nameValue)}) is not a string but ${typeof nameValue}.`,
+    );
+  }
+
+  public assertDefined(
+    data: ExecutableData,
+  ): asserts data is NonNullable<ExecutableData> {
+    this.assert(
+      () => data !== undefined && data !== null && Object.keys(data).length > 0,
+      'missing executable data',
+    );
+  }
+
+  public assert(
+    validationPredicate: () => boolean,
+    errorMessage: string,
+  ): asserts validationPredicate is (() => true) {
+    if (!validationPredicate()) {
+      this.throw(errorMessage);
+    }
+  }
+
+  public createContextualErrorMessage(errorMessage: string): string {
+    return this.createErrorMessage(errorMessage, this.context);
+  }
+
+  private throw(errorMessage: string): never {
+    throw new Error(
+      this.createContextualErrorMessage(errorMessage),
+    );
+  }
+}