fix(ui-truncate-text): remove lineHeight theme input, default v2 truncation to 1.2

[HerrTopi]

Summary

• Remove lineHeight as a theme/style input for v2 TruncateText: it's dropped from the TruncateTextStyle ComponentStyle union (props.ts), no longer emitted by styles.ts, and no longer threaded from index.tsx into the truncator options.
• Replace it with a module-level DEFAULT_LINE_HEIGHT = 1.2 constant in utils/truncate.ts. When the inherited computed line-height resolves to normal, truncation height is calculated as 1.2 * fontSize; a concrete line-height is still parsed from the computed style and used as-is.

Test Plan

• Render a v2 TruncateText in a container whose line-height is normal and confirm truncation lands on the right line (now driven by the 1.2 default).
• Render one with a concrete numeric/px line-height and confirm truncation is unchanged (no regression).

🤖 Generated with Claude Code

[github-actions]

PR Preview Action v1.8.1
Preview removed because the pull request was closed.
2026-07-17 12:10 UTC

[github-actions]

Visual regression report

✅ No changes.

Status	Count
Unchanged	32
Changed	0
New	0
Removed	0

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_{Baselines come from the visual-baselines branch. They refresh on every merge to master.}

[matyasf]

Looks good! Lets make sure that design removed the unused token