UI/refactor into separate classes

[lachlangrose]

This pull request includes a range of changes, primarily focused on new GUI components for the application, cleanup of configuration files, and minor code formatting updates. Below is a summary of the most significant changes:

New GUI Features

• Separates each UI element into separate objects
• Moves model/data logic/state to model and data managers.
• Added a new LoopWidget class in loopstructural/gui/loop_widget.py, which integrates tabs for "Modelling" and "Visualisation" functionalities. This serves as a central widget for managing these features.
• Introduced a BaseTab class in loopstructural/gui/modelling/base_tab.py to provide a consistent layout for tabs, with optional scrollable content and support for collapsible group boxes.
• Added a new export_tab.ui file in loopstructural/gui/modelling/export_tab.ui, defining a user interface for exporting models and interrogating geological data.

Configuration and Workflow Cleanup

• Removed unused hooks for black, isort, and flake8 from .pre-commit-config.yaml, simplifying the pre-commit configuration.
• Deleted trailing empty lines in several GitHub Actions workflow files, including .github/workflows/auto-labeler.yml, .github/workflows/documentation.yml, .github/workflows/linter.yml, .github/workflows/packager.yml, .github/workflows/releaser.yml, and .github/workflows/tester.yml. [1] [2] [3] [4] [5] [6]

Code Formatting Improvements

• Standardized docstring formatting for multi-line comments in docs/conf.py, loopstructural/__about__.py, and loopstructural/gui/dlg_settings.py. [1] [2] [3]
• Adjusted indentation and spacing in method definitions to improve readability, such as in plugin_metadata_as_dict() in loopstructural/__about__.py and __init__() in loopstructural/gui/dlg_settings.py. [1] [2]

Documentation Updates

• Removed redundant references to tools like black and isort in CONTRIBUTING.md, aligning with the changes in .pre-commit-config.yaml.