feat: Implement phases 6 to 9 of the review cycle fix process, including discovery, batching, parallel planning, execution, and completion

- Added Phase 6: Fix Discovery & Batching with intelligent grouping and batching of findings.
- Added Phase 7: Fix Parallel Planning to launch planning agents for concurrent analysis and aggregation of partial plans.
- Added Phase 8: Fix Execution for stage-based execution of fixes with conservative test verification.
- Added Phase 9: Fix Completion to aggregate results, generate summary reports, and handle session completion.
- Introduced new frontend components: ResizeHandle for draggable resizing of sidebar panels and useResizablePanel hook for managing panel sizes with localStorage persistence.
- Added PowerShell script for checking TypeScript errors in source code, excluding test files.

ccw/frontend/src/pages/orchestrator/useResizablePanel.ts

@@ -0,0 +1,136 @@
+// ========================================
+// useResizablePanel Hook
+// ========================================
+// Provides drag-to-resize functionality for sidebar panels.
+// Adapted from cc-wf-studio with Tailwind-friendly approach.
+
+import { useCallback, useEffect, useRef, useState } from 'react';
+
+const DEFAULT_MIN_WIDTH = 200;
+const DEFAULT_MAX_WIDTH = 600;
+const DEFAULT_WIDTH = 300;
+const DEFAULT_STORAGE_KEY = 'ccw-orchestrator.panelWidth';
+
+interface UseResizablePanelOptions {
+  minWidth?: number;
+  maxWidth?: number;
+  defaultWidth?: number;
+  storageKey?: string;
+  /** Direction of drag relative to panel growth. 'left' means dragging left grows the panel (right-side panel). */
+  direction?: 'left' | 'right';
+}
+
+interface UseResizablePanelReturn {
+  width: number;
+  isResizing: boolean;
+  handleMouseDown: (e: React.MouseEvent) => void;
+}
+
+/**
+ * Custom hook for resizable panel functionality.
+ *
+ * Features:
+ * - Drag-to-resize with mouse events
+ * - Configurable min/max width constraints
+ * - localStorage persistence
+ * - Prevents text selection during drag
+ */
+export function useResizablePanel(options?: UseResizablePanelOptions): UseResizablePanelReturn {
+  const minWidth = options?.minWidth ?? DEFAULT_MIN_WIDTH;
+  const maxWidth = options?.maxWidth ?? DEFAULT_MAX_WIDTH;
+  const defaultWidth = options?.defaultWidth ?? DEFAULT_WIDTH;
+  const storageKey = options?.storageKey ?? DEFAULT_STORAGE_KEY;
+  const direction = options?.direction ?? 'right';
+
+  // Initialize width from localStorage or use default
+  const [width, setWidth] = useState<number>(() => {
+    try {
+      const saved = localStorage.getItem(storageKey);
+      if (saved) {
+        const parsed = Number.parseInt(saved, 10);
+        if (!Number.isNaN(parsed) && parsed >= minWidth && parsed <= maxWidth) {
+          return parsed;
+        }
+      }
+    } catch {
+      // localStorage unavailable
+    }
+    return defaultWidth;
+  });
+
+  const [isResizing, setIsResizing] = useState(false);
+  const startXRef = useRef<number>(0);
+  const startWidthRef = useRef<number>(0);
+
+  // Handle mouse move during resize
+  const handleMouseMove = useCallback(
+    (e: MouseEvent) => {
+      const deltaX = e.clientX - startXRef.current;
+      // For 'right' direction (left panel), dragging right grows the panel
+      // For 'left' direction (right panel), dragging left grows the panel
+      const newWidth = direction === 'right'
+        ? startWidthRef.current + deltaX
+        : startWidthRef.current - deltaX;
+
+      const constrainedWidth = Math.max(minWidth, Math.min(maxWidth, newWidth));
+      setWidth(constrainedWidth);
+    },
+    [minWidth, maxWidth, direction]
+  );
+
+  // Handle mouse up to end resize
+  const handleMouseUp = useCallback(() => {
+    setIsResizing(false);
+  }, []);
+
+  // Handle mouse down to start resize
+  const handleMouseDown = useCallback(
+    (e: React.MouseEvent) => {
+      e.preventDefault();
+      setIsResizing(true);
+      startXRef.current = e.clientX;
+      startWidthRef.current = width;
+    },
+    [width]
+  );
+
+  // Set up global mouse event listeners
+  useEffect(() => {
+    if (isResizing) {
+      document.addEventListener('mousemove', handleMouseMove);
+      document.addEventListener('mouseup', handleMouseUp);
+
+      // Prevent text selection during drag
+      document.body.style.userSelect = 'none';
+      document.body.style.cursor = 'ew-resize';
+    } else {
+      document.removeEventListener('mousemove', handleMouseMove);
+      document.removeEventListener('mouseup', handleMouseUp);
+
+      document.body.style.userSelect = '';
+      document.body.style.cursor = '';
+    }
+
+    return () => {
+      document.removeEventListener('mousemove', handleMouseMove);
+      document.removeEventListener('mouseup', handleMouseUp);
+      document.body.style.userSelect = '';
+      document.body.style.cursor = '';
+    };
+  }, [isResizing, handleMouseMove, handleMouseUp]);
+
+  // Persist width to localStorage whenever it changes
+  useEffect(() => {
+    try {
+      localStorage.setItem(storageKey, width.toString());
+    } catch {
+      // localStorage unavailable
+    }
+  }, [width, storageKey]);
+
+  return {
+    width,
+    isResizing,
+    handleMouseDown,
+  };
+}