BN-84 | Use Zustand Store for DiagnosesForm

[mohan-13]

JIRA → BN-84

Description

This PR applies part of the changes for BN-84. This introduces the Zustand package which is used for central state management. The state management is introduced for the DiagnosisForm component. All the props for the form has been removed and the state management happens with Zustand store. This also address the adding an Inline error when certainty is not selected for diagnosis

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Key Features

• Adds Zustand library for State Management
• DiagnosisForm Component is refactored to use store instead of props based states.
• Inline error for Certainty is handled using store.

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Implementation Details

• State Management
  This PR introduces global state management for DiagnosisForm and ConsultationPad using Zustand library.

• Internationalisation

  • Added a new label which can be used when required dropdowns does not have a value selected. A key with en translation containing Please select a value has been added.

• Limitations

  • As a follow up PR, the InlineError for duplicate diagnosis will be refactored to disable the result from the combo box.
  • Also, Consultaion Pad tests will need to be refactored to remove redundant tests.

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Screenshots

Feature / State	Screenshot
Example: Before Refactoring
Example: After Refactoring

Note: Please ensure sensitive information is not included in screenshots.

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Important

Checklist

• Code adheres to project linting and formatting standards.
• New components added to Storybook.
• Tests written and passing (unit + integration).
• Labels and text support i18n.
• Follows accessibility and responsive design guidelines.
• PR reviewed by at least one other developer.

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Reviewer(s)

@bahnew/developers
Kindly review the proposed changes when convenient. Your feedback is appreciated.

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