fix: Search and select all issues

[azeezat]

Description

1. For the issue with the select all, I checked it further and realized the root cause was the use of a mutated array modifiedOptions in the selectAll function. I updated the array to use the optionsCopy which is the original array and it seems to work fine

2. For the issue with the placeholder, I added a new prop that would give the users the power to customize it at will. textInputProps will be able to take any kind of prop that would typically be accepted by any React Native's TextInput

 searchControls={{
              searchInputStyle: {
                backgroundColor: 'yellow',
                color: 'blue',
                fontWeight: '900',
              },
              textInputProps: {
                placeholder: 'Search anything here',
                placeholderTextColor: 'gray',
              },
            }}

Fixes #36

Type of change

Please delete options that are not relevant.

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published in downstream modules