Ensure that patched Plotly Figure does not break pane

[philippjfr]

Fixes holoviz/holoviews#6788

[Copilot]

Pull request overview

This PR updates the Plotly pane’s figure-linking logic so that it cooperates with Plotly figures that already define internal _send_* callback stubs, addressing holoviews/holoviews#6788.

Changes:

• Refactors _update_figure to work directly with self.object as fig and to early-return for None, dict objects, unchanged figures, or when link_figure is False.
• Switches the monkey-patching of Plotly Figure/FigureWidget message stubs (_send_addTraces_msg, _send_deleteTraces_msg, etc.) to only assign them if the attributes are not already present, avoiding overwriting existing implementations.
• Removes the explicit dependency on plotly.graph_objs in _update_figure, relying instead on structural checks (via hasattr) rather than concrete Plotly types.

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[codecov]

Codecov Report

❌ Patch coverage is 56.25000% with 7 lines in your changes missing coverage. Please review.
✅ Project coverage is 85.45%. Comparing base (ff75990) to head (738d679).
⚠️ Report is 3 commits behind head on main.

Files with missing lines	Patch %	Lines
panel/pane/plotly.py	56.25%	7 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #8397      +/-   ##
==========================================
- Coverage   86.08%   85.45%   -0.64%     
==========================================
  Files         349      349              
  Lines       54835    54821      -14     
==========================================
- Hits        47205    46845     -360     
- Misses       7630     7976     +346     

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[github-actions]

This pull request has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for related bugs.