ClimateMappedAfrica: User unable to click the search field

[koechkevin]

Description

currently, a user is unable to click input to search a location. This is caused by drawer backdrop which prevents actions on other visible elements even after setting a greater zIndex.
This PR changes drawer to persistent and updates styles to maintain how it was.

Fixes #1038

Type of change

Please delete options that are not relevant.

• Bug fix (non-breaking change which fixes an issue)

Screenshots

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation

[kilemensi]

👍🏽

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I can't seem to run this app without various errors. If it works on others i.e. if errors are only on my local then all good.

[kelvinkipruto]

LGTM

[kilemensi]

If the issues I raised are addressed/commented on @koechkevin, please go ahead with the PR; do not wait for my review.