Migrate Manhwa Scan to Mantraz Scan

[SamValdezS]

Checklist:

• Updated versionCode value in build.gradle.kts
• Updated baseVersionCode in build.gradle.kts (if updated multisrc theme code)
• Referenced all related issues in the PR body (e.g. "Closes #xyz")
• Set the contentWarning configuration in build.gradle.kts appropriately
• Have not changed source names
• Have explicitly kept the id if a source's name or language were changed
• Have tested the modifications by compiling and running the extension through Android Studio
• Have removed web_hi_res_512.png when adding a new extension
• This PR is AI-assisted, I have reviewed the changes manually and confirmed they are not slop

[SamValdezS]

Summary

Migrates the existing Manhwa Scan extension to Mantraz Scan.

• Updates the base URL to https://mantrazscan.co
• Renames the extension to Mantraz Scan
• Updates popular, latest, and text search
• Adds genre filtering
• Parses genre tags on manga details
• Retrieves all chapters, including those initially hidden by the website
• Parses chapter page images

Testing

• Built successfully with Gradle
• Tested in Mihon
• Verified popular, search, filters, manga details, genre tags, chapter lists, and reading pages

[Smol-Ame]

1. Change the extension to 1.6 format
2. Stop playing with the close & open button.

[SamValdezS]

Thank you for the feedback, and sorry for repeatedly toggling the PR status. This is my first contribution to this repository and I am still learning how to use GitHub properly.

I tested the extension on my phone using Mihon, and the main features worked correctly: popular/latest listings, search, genre filters, manga details, chapter lists, and reading pages.

I will update the extension to format 1.6, build and test it again, then mark the PR as ready for review. If there are any other repository-specific requirements I should follow, I would appreciate your guidance. Thank you for your patience.