chore: configure Dependabot for pnpm and GitHub Actions

[RahilAlam929]

Description

Configure Dependabot to keep pnpm dependencies and GitHub Actions dependencies up to date automatically.

Related Issue

Closes #383

Changes

• Added .github/dependabot.yml
• Enabled weekly pnpm dependency updates
• Enabled weekly GitHub Actions updates
• Limited open Dependabot PRs to 10
• Added dependencies and configuration labels
• Grouped pnpm development dependencies

Pre-Submission Checklist

• My commit messages follow the Conventional Commits format
• This PR is against the main branch

Type of Change

• chore: Build, CI/CD, or dependency updates

How Has This Been Tested?

Test Steps:

1. Reviewed the Dependabot configuration
2. Ran git diff --check
3. Verified the configuration is located at .github/dependabot.yml

Screenshots/Videos

Not applicable.

Additional Context

This addresses issue #383 by configuring automated weekly dependency updates for pnpm and GitHub Actions.

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[RahilAlam929]

Implemented the Dependabot configuration for issue #383.

• Added weekly pnpm dependency updates
• Added weekly GitHub Actions updates
• Set the open PR limit to 10
• Added dependencies and configuration labels
• Grouped pnpm development dependency updates

This addresses the requirements of #383.