Improve error messages for includePanelProcessor.ts

[AgentHagu]

What is the purpose of this pull request?

• Documentation update
• Bug fix
• Feature addition or enhancement
• Code maintenance
• DevOps
• Improve developer experience
• Others, please explain:
  Improve user experience (authors)

Overview of changes:
This PR improves the error messages of includePanelProcessor.ts by only logging the error message, rather than the entire error stack. This makes the errors more user-friendly and readable. The error message for URL src in popover is also updated to provide more details for authors to find the issue.

For example, currently the error would be logged as:

But the PR will update them to be logged as:

Anything you'd like to highlight/discuss:
These changes are derived from the PR #2639

Testing instructions:

Proposed commit message: (wrap lines at 72 characters)
Improve error messages for includePanelProcessor.ts

Currently, the error messages for includePanelProcessor.ts log both
the error message and the error stack. This may be confusing and
intimidating to users as it exposes some unnecessary details to them.

Let's update the logger to only log the error.message to hide the
error stack. Let's also update the error message for URLs in src to
be more user-friendly.

---

Checklist: ☑️

• Updated the documentation for feature additions and enhancements
• Added tests for bug fixes or features
• Linked all related issues
• No unrelated changes

---

Reviewer checklist:

Indicate the SEMVER impact of the PR:

• Major (when you make incompatible API changes)
• Minor (when you add functionality in a backward compatible manner)
• Patch (when you make backward compatible bug fixes)

At the end of the review, please label the PR with the appropriate label: r.Major, r.Minor, r.Patch.

Breaking change release note preparation (if applicable):

• To be included in the release note for any feature that is made obsolete/breaking

Give a brief explanation note about:

• what was the old feature that was made obsolete
• any replacement feature (if any), and
• how the author should modify his website to migrate from the old feature to the replacement feature (if possible).

[codecov]

Codecov Report

Attention: Patch coverage is 22.22222% with 7 lines in your changes missing coverage. Please review.

Project coverage is 52.80%. Comparing base (27d2f1a) to head (23a264a).
Report is 1 commits behind head on master.

Files with missing lines	Patch %	Lines
packages/core/src/html/includePanelProcessor.ts	22.22%	7 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #2703   +/-   ##
=======================================
  Coverage   52.80%   52.80%           
=======================================
  Files         130      130           
  Lines        7162     7162           
  Branches     1479     1573   +94     
=======================================
  Hits         3782     3782           
  Misses       3225     3225           
  Partials      155      155           

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