feat(query-builder): cancel condition mouse drag on Escape

[ivanvpetrov]

Closes #17749

Depends on #17744.

Description

Pressing Escape while dragging a Query Builder condition with the mouse now cancels the drag. The condition stays where it was and is not dropped when the mouse button is released.

• When a mouse drag starts, the dragged chip's dragDirective.cancelOnEscape is set to true (no new chip API).
• onMoveEnd() receives the chip's moveEnd args and does not drop when originalEvent.cancelled is true.
• During a mouse drag, Escape is no longer handled by the Query Builder's keyboard listener (the leftover TODO); the chip's igxDrag cancels the drag instead. Escape during a keyboard drag works as before.
• Because igxDrag stops the Escape that cancels the drag, it doesn't also close a surrounding dialog (e.g. Advanced Filtering).

Related fix: if another condition's drag indicator gets focus during a mouse drag, that focus is ignored, which is correct. But once the mouse drag ended without a drop (cancelled with Escape, or released outside a drop area), Arrow Up/Arrow Down on that indicator still did nothing until it was focused again. Now a keyboard drag starts for the focused indicator when the mouse drag ends. The release-outside-a-drop-area case was already broken before this PR.

Motivation / Context

#17744 added cancelDrag() and cancelOnEscape to igxDrag. This PR uses them in the Query Builder, as described in #17749.

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:

Query Builder (condition drag and drop)

How Has This Been Tested?

New and updated specs in query-builder.component.spec.ts, each failing before the change:

• Escape during a mouse drag cancels it: moveEnd reports cancelled, the source condition is shown again, the expression tree is unchanged, and releasing the mouse afterwards doesn't drop.

• cancelDrag() during a mouse drag doesn't drop.

• A mouse drag after a cancelled one drops as usual.

• After a mouse drag is cancelled with Escape, the drag indicator focused during it starts a keyboard drag with Arrow Up, and Space drops that condition.

• After a mouse drag is released outside a drop area, the drag indicator focused during it starts a keyboard drag (extended the existing test).

• Unit tests

• Manual testing

• Automated e2e tests

Test Configuration:

• Angular version: 22.2.0
• Browser(s): Chrome Headless 155
• OS: Windows 11

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]

🟢 Approval recommended

The focused implementation matches the stated requirements and includes comprehensive regression coverage.

0 open findings

What changed in this PR

Adds Escape cancellation for Query Builder condition mouse drags while preserving keyboard drag behavior and focus recovery.

Changes:

• Enables cancelOnEscape and prevents cancelled drags from committing.
• Restores keyboard dragging for indicators focused during an aborted mouse drag.
• Adds regression tests and changelog entries.

File	Description
query-builder.component.spec.ts	Tests cancellation, subsequent drags, and focus recovery.
query-builder-tree.component.html	Passes chip and move-end event data to the drag service.
query-builder-drag.service.ts	Implements cancellation handling and keyboard-drag recovery.
CHANGELOG.md	Documents the new behavior and related fix.

🧠 Review effort: Balanced

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