Fix/select menu admin settings

[harjibbolar26]

Description

This PR fixes the visual indication and seamless loading in the /dashboard/admin/settings route when a particular settings option is selected.

Closes #1335

Changes proposed

What were you told to do?

As a user I want to be able to see what I have selected when I am in the setting page

• Visually highlight selected menu
• Selecting a section should load and display the associated content without page reload.
• Selecting a new section deselects the previous one.
• Consistent behavior across different devices (desktop, tablet, mobile).
• Selected section must be accessible via keyboard navigation

What did you do?

• Fix the selected menu logic based on the pathname
• Crosscheck if all other issues are fixed

Check List (Check all the applicable boxes)

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• My code follows the code style of this project.
• This PR does not contain plagiarized content.
• The title and description of the PR is clear and explains the approach.
• I am making a pull request against the dev branch (left side).
• My commit messages styles matches our requested structure.
• My code additions will fail neither code linting checks nor unit test.
• I am only making changes to files I was requested to.

Screenshots/Videos

[github-actions]

Coverage Report

Status	Category	Percentage	Covered / Total
🔵	Lines	14.47%	782 / 5404
🔵	Statements	14.14%	784 / 5542
🔵	Functions	13.97%	215 / 1538
🔵	Branches	9.68%	229 / 2365

File Coverage

No changed files found.

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