V2 Restructure homepage (#4138)

Component Extraction & Context Refactor - Summary

  🔧 What We Did

- Extracted HomePage's 286-line monolithic component into focused parts
  - Created ToolPanel (105 lines) for tool selection UI
  - Created Workbench (203 lines) for view management
  - Created ToolWorkflowContext (220 lines) for centralized state
  - Reduced HomePage to 60 lines of provider setup
  - Eliminated all prop drilling - components use contexts directly

  🏆 Why This is Good

- Maintainability: Each component has single purpose, easy
debugging/development
- Architecture: Clean separation of concerns, future features easier to
add
- Code Quality: 105% more lines but organized/purposeful vs tangled
spaghetti code

---------

Co-authored-by: Connor Yoh <[email protected]>
Co-authored-by: James Brunton <[email protected]>

frontend/src/types/sidebar.ts

@@ -28,12 +28,6 @@ export interface SidebarProviderProps {
   children: React.ReactNode;
 }
 
-// QuickAccessBar related interfaces
-export interface QuickAccessBarProps {
-  onToolsClick: () => void;
-  onReaderToggle: () => void;
-}
-
 export interface ButtonConfig {
   id: string;
   name: string;