feat: add query parameter support to router handlers

[karthaj]

feat: Add Query Parameter Support to Router

This change adds comprehensive support for handling URL query parameters in the krouter package,
following the same patterns as existing header and path parameter handling.

Changes:

• Added query parameter support to Handler struct and configuration
• Enhanced Payload and HttpPayload structs with query parameter handling
• Introduced HandlerWithQueryParam option for configuring query parameters
• Added type-safe query parameter decoding and validation
• Extended Route struct to include query parameters in re-route messages

New Features:

1. Query Parameter Configuration:

   HandlerWithQueryParam("page", ParamTypeInt, true)    // required parameter
   HandlerWithQueryParam("sort", ParamTypeString, false) // optional parameter

2. Type-Safe Query Access:

   • In HTTP handlers: payload.Query("paramName")
   • Supports all existing parameter types (Int, String, UUID, custom types)
   • Automatic type conversion and validation

3. Re-routing Support:

   • Query parameters are preserved during re-routing
   • Maintains consistency with existing header and path parameter behavior
   • Example Usage:

   h := router.NewHandler("route1", encoder{}, preHandler, handler.Handle,
    HandlerWithQueryParam("page", ParamTypeInt, true),
    HandlerWithQueryParam("sort", ParamTypeString, false),
   )
   
   // Access in handler
   func (h *Handler) Handle(ctx context.Context, payload Payload) error {
      page := payload.Query("page").(int)
      sort := payload.Query("sort").(string)
      // ... handler logic
   }

Testing:

• Added comprehensive test coverage for query parameter handling
• Includes validation of required vs optional parameters
• Tests for type conversion and error cases
• Integration tests with the existing routing system
• This enhancement maintains backward compatibility while adding new functionality that follows the established patterns in the codebase.