Feature/improved search and results

[androidseb]

This PR proposes some changes to improve the search functionality by:

• allowing the search to be more specific by passing in a location latlng box
• making Location search results richer by returning the title and description fields

Pre-launch Checklist

• I made sure the project builds.
• I read the Contributor Guide and followed the process outlined there for submitting PRs.
• I updated pubspec.yaml with an appropriate new version according to the [pub versioning philosophy], or this PR is does not need version changes.
• I updated CHANGELOG.md to add a description of the change.
• I updated/added relevant documentation (doc comments with ///).
• I rebased onto main.
• I added new tests to check the change I am making, or this PR does not need tests.
• I made sure all existing and new tests are passing.
• I ran dart format . and committed any changes.
• I ran flutter analyze and fixed any errors.

How to use this

Until this PR is merged and integrated into the library's code, you can use the fork by updating your pubspec.yaml file like so:

  #geocoding: ^4.0.0
  geocoding:
    git:
      url: https://github.com/androidseb/flutter-geocoding
      ref: geocoding_sebs_fork_v4.0.0
      path: geocoding

Important note: waiting for confirmation of interest

I would like a confirmation from maintainers that they have interest in adding this functionality first (something as simple as a short reply saying "yes this would be a great addition"). Once I get that confirmation, I'll put further efforts into finalizing this PR.