Refactor to enforce strictNullChecks

This commit applies `strictNullChecks` to the entire codebase to improve
maintainability and type safety. Key changes include:

- Remove some explicit null-checks where unnecessary.
- Add necessary null-checks.
- Refactor static factory functions for a more functional approach.
- Improve some test names and contexts for better debugging.
- Add unit tests for any additional logic introduced.
- Refactor `createPositionFromRegexFullMatch` to its own function as the
  logic is reused.
- Prefer `find` prefix on functions that may return `undefined` and
  `get` prefix for those that always return a value.

tests/unit/presentation/components/Scripts/View/Cards/NonCollapsingDirective.spec.ts

@@ -9,34 +9,37 @@ describe('NonCollapsingDirective', () => {
       // arrange
       const element = createElementMock();
       // act
-      NonCollapsing.mounted(element, undefined, undefined, undefined);
+      if (!NonCollapsing.mounted) {
+        throw new Error('expected hook is missing');
+      }
+      NonCollapsing.mounted(element, undefined as never, undefined as never, undefined as never);
       // assert
       expect(element.hasAttribute(expectedAttributeName));
     });
   });
 
   describe('hasDirective', () => {
-    it('returns true if the element has expected attribute', () => {
+    it('returns `true` if the element has expected attribute', () => {
       // arrange
       const element = createElementMock();
-      element.setAttribute(expectedAttributeName, undefined);
+      element.setAttribute(expectedAttributeName, '');
       // act
       const actual = hasDirective(element);
       // assert
       expect(actual).to.equal(true);
     });
-    it('returns true if the element has a parent with expected attribute', () => {
+    it('returns `true` if the element has a parent with expected attribute', () => {
       // arrange
       const parent = createElementMock();
       const element = createElementMock();
       parent.appendChild(element);
-      element.setAttribute(expectedAttributeName, undefined);
+      element.setAttribute(expectedAttributeName, '');
       // act
       const actual = hasDirective(element);
       // assert
       expect(actual).to.equal(true);
     });
-    it('returns false if nor the element or its parent has expected attribute', () => {
+    it('returns `false` if nor the element or its parent has expected attribute', () => {
       // arrange
       const element = createElementMock();
       // act