test: enhance jest test setup and add documentation structure

Add vscrui to jest transform ignore patterns
Add crypto.getRandomValues mock for tests
Initialize cline documentation structure with required files

webview-ui/config-overrides.js

@@ -15,7 +15,7 @@ module.exports.jest = function(config) {
     
     // Configure transform ignore patterns for ES modules
     config.transformIgnorePatterns = [
-        '/node_modules/(?!(rehype-highlight|react-remark|unist-util-visit|unist-util-find-after|vfile|unified|bail|is-plain-obj|trough|vfile-message|unist-util-stringify-position|mdast-util-from-markdown|mdast-util-to-string|micromark|decode-named-character-reference|character-entities|markdown-table|zwitch|longest-streak|escape-string-regexp|unist-util-is|hast-util-to-text|@vscode/webview-ui-toolkit|@microsoft/fast-react-wrapper|@microsoft/fast-element|@microsoft/fast-foundation|@microsoft/fast-web-utilities|exenv-es6)/)'
+        '/node_modules/(?!(rehype-highlight|react-remark|unist-util-visit|unist-util-find-after|vfile|unified|bail|is-plain-obj|trough|vfile-message|unist-util-stringify-position|mdast-util-from-markdown|mdast-util-to-string|micromark|decode-named-character-reference|character-entities|markdown-table|zwitch|longest-streak|escape-string-regexp|unist-util-is|hast-util-to-text|@vscode/webview-ui-toolkit|@microsoft/fast-react-wrapper|@microsoft/fast-element|@microsoft/fast-foundation|@microsoft/fast-web-utilities|exenv-es6|vscrui)/)'
     ];
     
     return config;

webview-ui/src/setupTests.ts

@@ -1,14 +1,26 @@
 import '@testing-library/jest-dom';
 
-// Mock window.matchMedia
+// Mock crypto.getRandomValues
+Object.defineProperty(window, 'crypto', {
+  value: {
+    getRandomValues: function(buffer: Uint8Array) {
+      for (let i = 0; i < buffer.length; i++) {
+        buffer[i] = Math.floor(Math.random() * 256);
+      }
+      return buffer;
+    }
+  }
+});
+
+// Mock matchMedia
 Object.defineProperty(window, 'matchMedia', {
   writable: true,
   value: jest.fn().mockImplementation(query => ({
     matches: false,
     media: query,
     onchange: null,
-    addListener: jest.fn(), // Deprecated
-    removeListener: jest.fn(), // Deprecated
+    addListener: jest.fn(), // deprecated
+    removeListener: jest.fn(), // deprecated
     addEventListener: jest.fn(),
     removeEventListener: jest.fn(),
     dispatchEvent: jest.fn(),