[4.7.5] --score-media: fix various crashes

[RomanPudashkin]

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[RomanPudashkin]

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📥 Commits

Reviewing files that changed from the base of the PR and between 215d544 and 3994151.

📒 Files selected for processing (6)

• src/engraving/dom/instrument.cpp
• src/engraving/rw/read400/tread.cpp
• src/engraving/rw/read410/tread.cpp
• src/engraving/rw/read460/tread.cpp
• src/importexport/imagesexport/internal/svggenerator.cpp
• src/importexport/musicxml/internal/export/exportmusicxml.cpp

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📝 Walkthrough

Walkthrough

Instrument templates and legacy readers now create a default channel when no channels exist. The channel uses the default name and recognized MIDI program. Existing channels still receive the recognized program when unset. MusicXML export now resolves invalid percussion lines from the instrument drumset, with line 0 as fallback. SVG metric diagnostics use debug logging, and chord-line diagnostic output was removed.

Merge Risk: ⚪ Minimal · up to 39941

The changes are localized crash fixes, and no actionable merge-blocking risk remains after normal checks and review.

🚥 Pre-merge checks | ✅ 3 | ❌ 2

❌ Failed checks (2 warnings)

Check name	Status	Explanation	Resolution
Description check	⚠️ Warning	No pull request description was provided, so the required issue reference, change summary, motivation, and checklist are missing.	Add the required issue reference, a concise change summary and motivation, and complete each applicable checklist item.
Docstring Coverage	⚠️ Warning	Docstring coverage is 42.86% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (3 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly identifies the target branch, score-media area, and primary purpose of fixing crashes.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

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[DmitryArefiev]

Tested on LinuxUbuntu26.04 LTS. No crashes found