feat: Initialize organization chart web part with core functionality and configuration

- Added configuration files: config.json, copy-assets.json, package-solution.json, serve.json, write-manifests.json.
- Created gulpfile.js for build process.
- Implemented core logic in OrganizationChartCore.ts for account normalization and profile handling.
- Developed data service in OrganizationChartDataService.ts to fetch organization data from SharePoint User Profile Service.
- Defined types for user profiles and organization nodes in OrganizationChartTypes.ts.
- Created web part manifest for OrganizationChartWebPart.
- Built the main web part component with rendering logic and property pane configuration in OrganizationChartWebPart.ts.
- Developed React components for displaying the organization chart.
- Implemented styling for the organization chart in OrganizationChart.module.scss.
- Added localization support with English and German strings.
- Created unit tests for core functionalities in OrganizationChartCore.test.ts.
- Set up TypeScript and TSLint configurations for the project.

tests/OrganizationChartCore.test.ts

@@ -0,0 +1,30 @@
+import {
+  normalizeAccount,
+  normalizeCacheMinutes,
+  normalizeMaxDepth,
+  normalizeMaxPeople,
+  normalizeProfileUrl,
+  profileProperty,
+  uniqueAccounts
+} from '../src/webparts/organizationChart/OrganizationChartCore';
+import { IUserProfileProperty } from '../src/webparts/organizationChart/OrganizationChartTypes';
+
+declare const console: { log(message: string): void };
+let passed: number = 0;
+function assert(condition: boolean, message: string): void { if (!condition) { throw new Error(message); } passed++; }
+
+const properties: IUserProfileProperty[] = [
+  { Key: 'Department', Value: 'IT' },
+  { Key: 'Manager', Value: 'CONTOSO\\manager' }
+];
+assert(normalizeAccount(' CONTOSO\\user ') === 'CONTOSO\\user', 'Account must be trimmed.');
+assert(profileProperty(properties, 'department') === 'IT', 'Profile-property lookup must ignore casing.');
+assert(profileProperty(properties, 'Office') === '', 'Missing profile properties must be empty.');
+assert(uniqueAccounts(['A', 'a', 'B', 'C'], 'B', 10).join(',') === 'A,C', 'Accounts must be unique and excludable.');
+assert(normalizeMaxDepth(0) === 6 && normalizeMaxDepth(20) === 10, 'Tree depth must be constrained.');
+assert(normalizeMaxPeople(1) === 10 && normalizeMaxPeople(900) === 500, 'Person count must be constrained.');
+assert(normalizeCacheMinutes(-1) === 0 && normalizeCacheMinutes(300) === 120, 'Cache duration must be constrained.');
+assert(normalizeProfileUrl('javascript:alert(1)', 'http://portal') === '', 'Unsafe profile URLs must be rejected.');
+assert(normalizeProfileUrl('/my/person.aspx', 'http://portal') === '/my/person.aspx', 'Server-relative URLs must be retained.');
+
+console.log('Organization chart core tests passed: ' + passed);