feat: Add comprehensive read-only Bevy Inspector with remote inspection capabilities

[jbuehler23]

(Almost) A read-only bevy editor!

• Added a new dedicated bevy_editor crate with modular architecture for real-time entity and component inspection
• Implemented remote connection system using bevy_remote protocol for inspecting external Bevy applications
• Created comprehensive UI widget system including ScrollViewBuilder, CoreScrollArea, ExpansionButton, BasicPanel, and ScrollableContainer
• Developed entity list and component inspector panels with expandable, hierarchical component viewing
• Established theming system with EditorTheme struct for consistent visual styling
• Added intelligent component formatting with specialized support for Bevy types (Vec2/Vec3/Quat, Colors, Entity IDs)
• Implemented mouse wheel scrolling and keyboard shortcuts (E/T/C keys) for enhanced navigation
• Created HTTP client with automatic connection management and status monitoring
• Added comprehensive documentation and examples for modular editor usage

Objective

This PR addresses the need for a robust, standalone entity inspector and editor for Bevy applications that can connect to remote processes via bevy_remote.

• Remote inspection capabilities for debugging live applications
• Modular architecture allowing individual components to be used separately
• Modern UI with responsive design and intuitive controls

Solution

The solution introduces a new bevy_editor crate with a modular architecture:

Core Architecture

• EditorPlugin: Main plugin that orchestrates all editor functionality
• Panel System: Individual UI panels (EntityListPlugin, ComponentInspectorPlugin) that can be used independently
• Widget Library: Reusable UI components with bevy_core_widgets integration
• Remote Client: HTTP client implementing the bevy_remote protocol
• Formatting System: Intelligent component data formatting and display
• Theme System: Consistent styling across all editor components

Key Features Implemented

1. Remote Connection System (src/remote/):

   • HTTP client with automatic connection management
   • Support for bevy_remote protocol
   • Real-time connection status monitoring
   • Automatic reconnection on connection loss

2. UI Widget Library (src/widgets/):

   • ScrollViewBuilder for high-level scrollable containers
   • CoreScrollArea for low-level scroll implementations
   • ExpansionButton for collapsible content
   • BasicPanel for structured content areas
   • ScrollableContainer with mouse wheel support

3. Panel System (src/panels/):

   • EntityListPlugin: Entity browser with selection and filtering
   • ComponentInspectorPlugin: Detailed component viewer with hierarchical expansion

4. Component Formatting (src/formatting/):

   • Specialized formatting for Bevy types (Transform, Vec3, Color, etc.)
   • Hierarchical field breakdown for complex components
   • Smart type recognition and display

5. Theme System (src/themes/):

   • EditorTheme struct for consistent styling
   • Dark theme with professional appearance
   • Integration with bevy_feathers compatibility

Testing

Manual Testing Performed

• Inspector connects successfully to remote bevy_remote servers
• Entity list displays and updates in real-time
• Component inspector shows hierarchical component data
• Mouse wheel scrolling works smoothly
• Keyboard shortcuts (E/T/C) function correctly
• Connection status indicators update appropriately
• UI scales properly on different window sizes

Testing Instructions for Reviewers

1. Basic Inspector Test:

   cargo run --example inspector --package bevy_editor

2. Remote Connection Test:

   # Terminal 1: Start a server with bevy_remote
   cargo run --example server --features bevy_remote
   
   # Terminal 2: Start the inspector
   cargo run --example inspector --package bevy_editor

3. Individual Component Test:

   // Test individual panels
   use bevy_editor::panels::EntityListPlugin;
   App::new().add_plugins(EntityListPlugin).run();

Platforms Tested

• macOS (primary development)
• Windows

Areas Needing Additional Testing

• Network connectivity edge cases
• Large entity counts (1000+ entities)
• Complex nested component structures
• Multi-window scenarios

---

Showcase

The new Bevy Editor provides a professional entity inspection experience similar to other game engines:

Key Features Demonstrated

Two-Panel Layout: Clean entity list on the left, detailed component inspector on the right

• Entity browser with real-time updates
• Hierarchical component viewing with expand/collapse
• Connection status indicator
• Smooth mouse wheel scrolling

Smart Component Formatting:

// Example of formatted component display
[bevy_transform] Transform
  ▼ translation: (0.00, 1.37, 0.00)
    x: 0.000
    y: 1.367  
    z: 0.000
  ▼ rotation: (0.00, 0.00, 0.00, 1.00)
  ▼ scale: (1.00, 1.00, 1.00)

[bevy_camera] Camera  
  ▼ projection: Perspective
  ▼ viewport: Some(Viewport)

[server] Cube
  value: Entity(1)

Modular Usage:

// Use the complete editor
use bevy_editor::prelude::*;
App::new().add_plugins(EditorPlugin).run();

// Or individual components
use bevy_editor::panels::{EntityListPlugin, ComponentInspectorPlugin};
use bevy_editor::widgets::WidgetsPlugin;
App::new()
    .add_plugins((EntityListPlugin, ComponentInspectorPlugin, WidgetsPlugin))
    .run();

Remote Connection:

// Automatic connection to bevy_remote servers
// No manual configuration needed - connects to localhost:15702 by default
// Displays live entity and component data from remote applications

[github-actions]

You added a new example but didn't add metadata for it. Please update the root Cargo.toml file.

[IQuick143]

Added X-Controversial just because of new crate.

[github-actions]

You added a new example but didn't add metadata for it. Please update the root Cargo.toml file.

[jbuehler23]

Added X-Controversial just because of new crate.

In all honesty, it's likely this gets moved to bevy_dev_tools. Just haven't had the time yet!

[Zeophlite]

Why aren't src/widgets/ in bevy_core_widgets ?