feat: Enhance transition api

[q32757468]

Description

不同动画形式的效果：

写了example，也可以拉下来看各种形式的动画效果

Motivation and Context

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Enhancement (changes that improvement of current feature or performance)
• Refactoring (changes that neither fixes a bug nor adds a feature)
• Test Case (changes that add missing tests or correct existing tests)
• Code style optimization (changes that do not affect the meaning of the code)
• Docs (changes that only update documentation)
• Chore (changes that don't modify src or test files)

Self Check before Merge

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• All new and existing tests passed.

[gemini-code-assist]

Summary of Changes

Hello @q32757468, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request introduces a comprehensive enhancement to the animation system, providing developers with more granular control over how elements transition within the graph. It expands the transition API with new options for iteration, direction, and fill behavior, and integrates a declarative approach for defining animations directly on cells. Additionally, new examples have been added to demonstrate these powerful features for both nodes and edges, along with a new view:render event to improve animation synchronization.

Highlights

• Enhanced Animation API: The core animation API has been significantly extended to support advanced control over transitions, including iterations for repeating animations, direction (normal, reverse, alternate, alternate-reverse) for playback control, and fill (none, forwards) to define how styles are applied after an animation completes.
• Declarative Transitions for Cells: Cells can now define transitions declaratively via a new transition property in their Properties. When a cell with this property is added to the graph, its specified transitions will automatically start, simplifying animation setup.
• New Animation Examples: Several new examples have been added to showcase the enhanced animation capabilities: AnimateElementExample demonstrates native SVG animations, ComplexTransitionExample (renamed from TransitionExample) shows advanced node transitions, EdgeTransitionExample illustrates various edge animations, and TransitionConfExample highlights different ways to configure animations.
• View Render Event: A new view:render event is now emitted by NodeView and EdgeView after their initial rendering. This provides a precise hook for animations or other logic that depends on the view being fully rendered in the DOM.
• Default fill for transition method: The cell.transition() method now defaults the fill option to 'forwards', ensuring that the animated property retains its final value after the transition completes by default.

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[gemini-code-assist]

Code Review

This pull request significantly enhances the animation API by incorporating features from the Web Animations API, such as iterations, direction, and fill options. This enables more complex and repeatable animations, including infinite loops. The changes also introduce support for declarative animations on cells via a transition property and a new view:render event, which is useful for DOM-based animations. The new examples effectively demonstrate these powerful new features. The core animation logic has been well-refactored to accommodate these enhancements. I have a couple of suggestions to improve code maintainability in src/model/cell.ts.

[codecov-commenter]

Codecov Report

❌ Patch coverage is 85.00000% with 9 lines in your changes missing coverage. Please review.
✅ Project coverage is 81.94%. Comparing base (0f0f5f5) to head (86294d0).

Files with missing lines	Patch %	Lines
src/model/animation.ts	87.50%	4 Missing and 1 partial ⚠️
src/model/cell.ts	77.77%	4 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #4848      +/-   ##
==========================================
- Coverage   81.94%   81.94%   -0.01%     
==========================================
  Files         327      327              
  Lines       37972    38019      +47     
  Branches     7632     7639       +7     
==========================================
+ Hits        31116    31153      +37     
- Misses       6832     6841       +9     
- Partials       24       25       +1     

Flag	Coverage Δ
x6	81.94% <85.00%> (-0.01%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files with missing lines	Coverage Δ
src/view/cell/type.ts	100.00% <ø> (ø)
src/view/edge/index.ts	59.63% <100.00%> (+0.02%)	⬆️
src/view/node/index.ts	64.76% <100.00%> (+0.03%)	⬆️
src/model/cell.ts	77.78% <77.77%> (-0.04%)	⬇️
src/model/animation.ts	90.41% <87.50%> (-2.34%)	⬇️

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