feat(angular): Add Angular 20 compatibility

[thakkarkeyur]

Summary

Adds Angular 20 compatibility to dockview-angular while maintaining backward compatibility with Angular 14+.

Problem

Angular 20 introduced stricter validation for standalone components. The current implementation causes compilation errors:

• NG6008: Component is standalone and cannot be declared in an NgModule
• NG6004: Can't be exported from NgModule without being imported first

Solution

Implements a hybrid standalone pattern:

• Added standalone: true to all four components (DockviewAngular, GridviewAngular, PaneviewAngular, SplitviewAngular)
• Updated DockviewAngularModule to import components instead of declaring them
• This pattern works with both NgModule and standalone component usage

Changes

• dockview-angular.component.ts - Added standalone: true
• gridview-angular.component.ts - Added standalone: true
• paneview-angular.component.ts - Added standalone: true
• splitview-angular.component.ts - Added standalone: true
• dockview-angular.module.ts - Changed from declarations to imports

Testing

• Verified compilation with Angular 20.3.12 and TypeScript 5.8
• Tested with minimal Angular 20 application
• Confirmed backward compatibility maintained (Angular 14-19)
• Zero breaking changes for existing users

Breaking Changes

None - fully backward compatible.

[codesandbox-ci]

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Latest deployment of this branch, based on commit 842ca16:

Sandbox	Source
dockview-app	Configuration
editor-gridview	Configuration
externaldnd-dockview	Configuration
fullwidthtab-dockview	Configuration
iframe-dockview	Configuration
keyboard-dockview	Configuration
nativeapp-dockview	Configuration
rendering-dockview	Configuration

[thakkarkeyur]

Critical Bug Fix Added

Adds an important bug fix to this PR that addresses a fundamental issue with the AngularRenderer.

Problem

The AngularRenderer was using hasOwnProperty() to check if properties exist before setting them. This doesn't work with TypeScript getter/setter properties because they're defined on the prototype chain, not as own properties.

This bug prevented header action components (and any components using getters/setters) from receiving their props from dockview-core.

Solution

Commit: 842ca16

• Changed property detection: Replaced hasOwnProperty() with the in operator to check the entire prototype chain
• Made init() idempotent: Updated init method to handle multiple initialization calls
• Added documentation: Clarified the initialization pattern in component-factory.ts

Files Changed

• packages/dockview-angular/src/lib/utils/angular-renderer.ts
• packages/dockview-angular/src/lib/utils/component-factory.ts

Impact

This enables reactive patterns with property setters:

export class HeaderActionsComponent {
    private _api: any;
    
    get api() { return this._api; }
    set api(value: any) {
        this._api = value;
        this.setupListeners();  // Now this works!
    }
}

Testing

• Verified with Angular 20.3.12
• Confirmed header action components receive props correctly
• Tested getter/setter properties work as expected
• Backward compatible with regular properties

This is a general bug fix that benefits all Angular versions, not just Angular 20.