Add search functionality

[dev-rashedin]

Description
A search feature needs to be implemented to help users quickly find content, pages, or services within the site.

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Expected behavior
Users should be able to type in a search bar and see relevant results instantly (or after submission).

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Additional context

• This is a planned feature for a future update.
• Consider integrating a lightweight client-side search (e.g., Fuse.js) or server-side search depending on data complexity.