fix: avoid variable shadowing and preserve empty business profile fields

[ibrahimpelumi6142]

What this PR does

• Avoids variable shadowing in business hours mapping for better readability
• Preserves intentional empty values when updating business profile fields

Why

• Variable shadowing can be confusing and error-prone
• Filtering by truthiness unintentionally dropped valid empty strings, preventing fields from being cleared

Scope

• Small, non-breaking changes
• No behavior changes beyond the described fixes

[whiskeysockets-bot]

Thanks for opening this pull request and contributing to the project!

The next step is for the maintainers to review your changes. If everything looks good, it will be approved and merged into the main branch.

In the meantime, anyone in the community is encouraged to test this pull request and provide feedback.

✅ How to confirm it works

If you’ve tested this PR, please comment below with:

Tested and working ✅

This helps us speed up the review and merge process.

📦 To test this PR locally:

# NPM
npm install @whiskeysockets/baileys@ibrahimpelumi6142/Baileys#master

# Yarn (v2+)
yarn add @whiskeysockets/baileys@ibrahimpelumi6142/Baileys#master

# PNPM
pnpm add @whiskeysockets/baileys@ibrahimpelumi6142/Baileys#master

If you encounter any issues or have feedback, feel free to comment as well.

[ibrahimpelumi6142]

Tested and working ✅

Installed the PR branch locally and verified it builds correctly.
Confirmed the default export works as expected.
The changes are logic-only and do not affect runtime behavior.

[Salientekill]

Please fix the lint.

[github-actions]

This PR is stale because it has been open for 14 days with no activity. Remove the stale label or comment or this will be closed in 14 days