Reorganizes the internal server structure to improve code organization and maintainability.

Changes

Handler Reorganization

• Moved: JsonRpc/Handler → Server/Handler/JsonRpcHandler
• Reorganized: Server/RequestHandler/ → Server/Handler/Request/
• Reorganized: Server/NotificationHandler/ → Server/Handler/Notification/
• Moved: MethodHandlerInterface → Server/Handler/ namespace

Transport Structure

• Moved: TransportInterface → Server/Transport/ namespace
• Consolidated: All transport-related code in one location

Data Structure

• Moved: Page.php → Schema/ namespace
• Rationale: It's a data structure concern, not server logic

Why

Better Organization

• Logical grouping: Related code is now co-located
• Predictable structure: Easier to find and understand code
• Cleaner namespaces: More intuitive import statements

Separation of Concerns

• Server-specific: JsonRpcHandler is server implementation, not global protocol
• Protocol-agnostic: MessageFactory stays in JsonRpc/ for reusability
• Data vs Logic: Page is a data structure, not server logic

Breaking Changes

• Internal only: No public API changes
• Import updates: All internal references updated
• Namespace changes: Internal classes moved to new namespaces