Add Dynamic Poll Web Part with core functionality and styling

- Initialize Gulp build process with gulpfile.js
- Create package.json for project dependencies and scripts
- Add TypeScript declarations for SCSS modules
- Implement DynamicPollWebPart with property pane configuration
- Create PollDataService for SharePoint list interactions
- Develop core polling logic in PollCore.ts
- Define types for polls and answers in PollTypes.ts
- Create React components for DynamicPoll UI
- Add localization support for English and German
- Implement unit tests for core polling functionality
- Set up TypeScript and TSLint configurations

tests/PollCore.test.ts

@@ -0,0 +1,34 @@
+import { calculatePollResults, findUserAnswer, selectActivePoll } from '../src/webparts/dynamicPoll/PollCore';
+import { IPoll, IPollAnswer } from '../src/webparts/dynamicPoll/PollTypes';
+
+let passed: number = 0;
+function assert(name: string, condition: boolean): void {
+  if (!condition) { throw new Error('FAILED: ' + name); }
+  passed++; console.log('OK:', name);
+}
+function poll(value: any): IPoll { return value as IPoll; } // tslint:disable-line:no-any
+
+const now: Date = new Date('2026-08-23T12:00:00Z');
+const selected: IPoll = selectActivePoll([
+  poll({ id: 1, question: 'old', options: ['A'], isActive: true,
+    startDate: new Date('2026-08-20T00:00:00Z'), endDate: new Date('2026-08-22T00:00:00Z') }),
+  poll({ id: 2, question: 'current', options: ['A', 'B'], isActive: true,
+    startDate: new Date('2026-08-23T00:00:00Z'), endDate: new Date('2026-08-24T00:00:00Z') }),
+  poll({ id: 3, question: 'future', options: ['A'], isActive: true,
+    startDate: new Date('2026-08-24T00:00:00Z') })
+], now);
+assert('current poll is selected by activation window', !!selected && selected.id === 2);
+
+const answers: IPollAnswer[] = [
+  { id: 1, userKey: 'one@contoso.local', answer: 'A' },
+  { id: 2, userKey: 'two@contoso.local', answer: 'B' },
+  { id: 3, userKey: 'three@contoso.local', answer: 'A' },
+  { id: 4, userKey: 'legacy@contoso.local', answer: 'Removed option' }
+];
+const results = calculatePollResults(['A', 'B'], answers);
+assert('votes are counted per configured option', results[0].votes === 2 && results[1].votes === 1);
+assert('invalid legacy answer is excluded from percentage', results[0].percentage === 67 && results[1].percentage === 33);
+assert('user lookup is case insensitive', findUserAnswer(answers, 'ONE@CONTOSO.LOCAL') === 'A');
+assert('unknown user has no answer', findUserAnswer(answers, 'unknown@contoso.local') === '');
+console.log('DynamicPoll core tests passed:', passed);
+