Fix lipgloss padding on long CLI error messages

[holyfuchs]

Closes #2331

Summary

When handleError passes a multi-line error message through lipgloss's Render, lipgloss normalizes every line to the width of the longest line, producing hundreds of trailing spaces that make the output completely unreadable.
This was most visible with flow test assertion failures containing a full Cadence transaction error chain serialized with literal \n sequences.

Fix

Added renderErrorMsg which:

1. Unescapes literal \n sequences (common in serialized Cadence runtime errors)
2. Styles each line individually via branding.ErrorStyle.Render(line) — passing a multiline block to lipgloss triggers the padding behavior, but single lines are safe

All errorMessageStyle.Render(...) calls in handleError now go through this function. The unused errorMessageStyle and descriptionStyle vars were also removed.

[github-actions]

Dependency Review

✅ No vulnerabilities or license issues or OpenSSF Scorecard issues found.

Scanned Files

None

[codecov-commenter]

Codecov Report

❌ Patch coverage is 0% with 15 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
internal/command/result.go	0.00%	15 Missing ⚠️

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