fix(tree): render deferred selection in zoneless apps

[viktorkombov]

Closes #17444

Description

Fixes Tree checkbox states not updating after deferred selection changes in
zoneless applications.

Covers initial selection and cascading selection after removing a child node.

Type of Change (check all that apply):

• Bug fix
• New functionality
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Refactoring (no functional changes)
• Documentation
• Demos
• CI/CD
• Tests
• Changelog
• Skills/Agents

Component(s) / Area(s) Affected:

How Has This Been Tested?

• Unit tests
• Manual testing
• Automated e2e tests

Test Configuration:

• Angular version:
• Browser(s):
• OS:

Screenshots / Recordings

Checklist:

• All relevant tags have been applied to this PR
• This PR includes unit tests covering all the new code (test guidelines)
• This PR includes API docs for newly added methods/properties (api docs guidelines)
• This PR includes feature/README.MD updates for the feature docs
• This PR includes general feature table updates in the root README.MD
• This PR includes CHANGELOG.MD updates for newly added functionality
• This PR contains breaking changes
• This PR includes ng update migrations for the breaking changes (migrations guidelines)
• This PR includes behavioral changes and the feature specification has been updated with them
• Accessibility (ARIA, keyboard navigation, focus management) has been verified

[Copilot]

Pull request overview

Fixes IgxTree checkbox rendering in zoneless Angular apps when selection is applied via the deferred forceSelect path (e.g., initial [selected] bindings and cascading updates after node removal).

Changes:

• Injects ChangeDetectorRef in IgxTreeComponent and calls markForCheck() after deferred selection is applied.
• Adds zoneless unit tests covering (1) initial selected node rendering and (2) cascading selection update after removing an unselected child node.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
projects/igniteui-angular/tree/src/tree/tree.component.ts	Triggers change detection scheduling after applying deferred selection to keep checkbox UI in sync in zoneless apps.
projects/igniteui-angular/tree/src/tree/tree-selection.spec.ts	Adds zoneless regression tests for initial selection rendering and cascading selection after node deletion.

[mddragnev]

The issue is fixed indeed. However, I see another issue. If you later show the second tree-item which was never selected, the state of the tree does not go to indeterminate. This is issue is not regarding the zoneless and it is reproducible in Zone based CD, so it should be logged separately

[Copilot]

Pull request overview

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

[Copilot]

Pull request overview

Copilot reviewed 2 out of 2 changed files in this pull request and generated no new comments.

[Copilot]

Pull request overview

Copilot reviewed 3 out of 3 changed files in this pull request and generated no new comments.

[Copilot]

Pull request overview

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

[Copilot]

Pull request overview

Copilot reviewed 2 out of 2 changed files in this pull request and generated no new comments.

[Copilot]

Pull request overview

Copilot reviewed 2 out of 2 changed files in this pull request and generated no new comments.

Comments suppressed due to low confidence (1)

projects/igniteui-angular/tree/src/tree/tree.component.ts:87

• ChangeDetectorRef is injected as optional, but for a component it should always be available. Making it optional can silently disable the CD notification that this fix relies on, making future regressions harder to detect. Prefer a required injection here.

    private cdr = inject(ChangeDetectorRef, { optional: true });