Fix collapsed call card text overlapping controls

[xhon-pelushi]

Summary

• Collapsed call card: give the "started a call" label layout_weight with single-line ellipsis so it no longer crowds the controls.
• Theme the close button with the primary color for clearer visibility in the collapsed state.

Fixes #5066

Test plan

• Start/join a call so the call-started banner appears, then collapse it.
• Confirm the label truncates cleanly and the expand/close controls remain visible and tappable.
• Rotate / switch theme and confirm the card still lays out correctly.

[mahibi]

thank you @xhon-pelushi 👍

[github-actions]

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