Standardize header styles for test panel

KU
6h ago
+37-5

Align section header font properties and toggle indicators across both the Add a case and Test results drawers for visual consistency.

Closes #298

Summary by cubic

Standardizes header typography and toggle indicators across the Add a case and Test results drawers so both panels look and behave consistently. Closes #298.

  • Replaces the text "v" chevron with a shared CSS-drawn arrow that rotates 90° when the panel opens.
  • Hides the native <details> marker and applies the same font, padding, and alignment to both headers.