feat: Add defaultBottomNavigationController & bottomNavigationView

[divyanshub024]

Description

This PR adds the ability to show the widget when the corresponding item is selected from the BottomNavigationBar.

Here is an example

{
  "type": "defaultBottomNavigationController",
  "length": 3,
  "child": {
    "type": "scaffold",
    "appBar": {
      "type": "appBar",
      "title": {
        "type": "text",
        "data": "Bottom Navigation Screen"
      }
    },
    "body": {
      "type": "bottomNavigationView",
      "children": [
        {
          "type": "center",
          "child": {
            "type": "text",
            "data": "Home",
            "style": {
              "fontSize": 24
            }
          }
        },
        {
          "type": "center",
          "child": {
            "type": "text",
            "data": "Search",
            "style": {
              "fontSize": 24
            }
          }
        },
        {
          "type": "center",
          "child": {
            "type": "text",
            "data": "Profile",
            "style": {
              "fontSize": 24
            }
          }
        }
      ]
    },
    "bottomNavigationBar": {
      "type": "bottomNavigationBar",
      "items": [
        {
          "type": "navigationBarItem",
          "label": "Home",
          "icon": {
            "type": "icon",
            "iconType": "material",
            "icon": "home"
          }
        },
        {
          "type": "navigationBarItem",
          "label": "Search",
          "icon": {
            "type": "icon",
            "iconType": "material",
            "icon": "search"
          }
        },
        {
          "type": "navigationBarItem",
          "label": "Profile",
          "icon": {
            "type": "icon",
            "iconType": "material",
            "icon": "account_circle"
          }
        }
      ]
    }
  }
}

Type of Change

• New feature (non-breaking change which adds functionality)
• Bug fix (non-breaking change which fixes an issue)
• Breaking change (fix or feature that would cause existing functionality to change)
• Code refactor
• Build configuration change
• Documentation
• Chore

[i-asimkhan]

Hey looks good.