Fix filled arrowhead color for lines

[pyonpyoco]

Resolves: #33723

Filled arrowheads for lines used the item color instead of the effective line color.
This PR uses the same color for filled begin/end arrowheads as the line body.

Manual test:
Changed a line color and confirmed that the filled arrowhead follows it.

• I signed the CLA as username:
• The title of the PR describes the problem it addresses.
• Each commit's message describes its purpose and effects, and references the issue it resolves. If changes are extensive, there is a sequence of easily reviewable commits.
• The code in the PR follows the coding rules.
• I understand all aspects of the code I'm contributing and I'm able to explain it if requested.
• The code compiles and runs on my machine, preferably after each commit individually. I have manually tested and verified that my changes fulfil their intended purpose.
• No prior attempts to resolve this problem exist, or if they do, I listed them in my PR description and described how I avoided repeating past mistakes.
• There are no unnecessary changes.
• I created a unit test or vtest to verify the changes I made (if applicable).

[coderabbitai]

📝 Walkthrough

Walkthrough

This PR modifies arrow hook fill color rendering in TDraw::drawTextLineBaseSegment. Two code blocks are updated to use the segment's computed line color instead of item->curColor(opt) when painting filled arrow hooks at both the begin and end positions. The change affects only the ARROW_FILLED hook type cases and standardizes the color source for consistent arrow hook rendering.

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title 'Fix filled arrowhead color for lines' directly and concisely describes the main change in the changeset.
Linked Issues check	✅ Passed	The code changes directly address the requirement in issue #33723 by fixing filled arrowhead color to match the line's effective color instead of using the default item color.
Out of Scope Changes check	✅ Passed	All changes are focused on the specific issue of filled arrowhead color; no out-of-scope modifications were introduced.
Description check	✅ Passed	The PR description includes issue reference, clear problem statement, motivation, manual testing verification, and a screenshot demonstrating the fix, with all required checklist items marked complete.

_{✏️ Tip: You can configure your own custom pre-merge checks in the settings.}

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

Warning

Review ran into problems

🔥 Problems

Linked repositories: Your configuration references 1 linked repositories, but your current plan allows 0. Analyzed ``, skipped musescore/muse_framework.git.

---

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

• X
• Mastodon
• Reddit
• LinkedIn

_{Comment @coderabbitai help to get the list of available commands and usage tips.}