refactor: simplify complex methods and improve code quality

[mustalk]

This pull request focuses on significant refactoring efforts across NewMissionContent, MissionResultCard, and NewMissionViewModel to address code complexity, improve maintainability, and enhance adherence to code quality standards, primarily driven by Detekt findings.

Key Changes:

1. NewMissionContent Refactoring:

• Extracted UI sections into focused, reusable sub-components:
  • InputModeSelector: Manages the UI for switching between input modes.
  • InputContentSection: Handles the rendering logic for different input content (JSON/Manual).
  • ActionButtonsSection: Encapsulates the mission execution buttons and related controls.
• Removed the @Suppress("CyclomaticComplexMethod") annotation as the complexity has been resolved through decomposition.

2. MissionResultCard Simplification:

• Decomposed the MissionResultCard composable for better clarity and reduced complexity:
  • MissionStatusRow: Dedicated to displaying the mission status (success/failure) and rover position/orientation.
  • ExpandableInputSection: Manages the display of collapsible input data within the result card.
• Removed the @Suppress("CyclomaticComplexMethod") annotation due to successful refactoring.

3. NewMissionViewModel Architecture Optimization:

• Delegated specific responsibilities from the ViewModel to dedicated handler/manager classes:
  • StateManager: Manages UI state updates, message clearing, and input mode switching.
  • FieldUpdateHandler: Handles updates to all form field inputs (JSON, plateau dimensions, rover commands).
  • ValidationHandler: Encapsulates all input validation logic.
  • MissionExecutor: Contains the core business logic for executing rover missions (both network and local).
• This significantly slims down the NewMissionViewModel, reducing it to a more focused public interface that coordinates these helper classes.
• Added a targeted @Suppress("TooManyFunctions") to the ViewModel with a clear justification, as its role is now primarily delegation, which is an acceptable pattern.

Benefits & Impact:

• Improved SOLID Principle Adherence: Notably Single Responsibility Principle (SRP) by breaking down large components and ViewModels.
• Enhanced Separation of Concerns: Clearer boundaries between UI rendering, state management, input handling, validation, and business logic.
• Increased Testability: Smaller, focused units (sub-components and delegated handlers) are significantly easier to unit test in isolation.
• Reduced Complexity: Resolved all Detekt CyclomaticComplexMethod issues and generally made the codebase easier to understand and maintain.
• Scalability & Future-Proofing: These changes provide a cleaner foundation, making it easier to introduce new features or transition towards a multi-module architecture in the future.

Testing:

• All automated tests (unit and integration) pass.
• Manual testing confirmed existing functionality remains unchanged and performs as expected.