style: polish investigation workspace
- Summary panel: hide meaningless metrics (questions answered/remaining) until genuinely in progress; remove placeholder timestamps
- Understanding card: increased visual importance via larger heading, lighter border, more padding
- History section: reduced labels to brief forms ('History', 'Situation'), removed uppercase decorative labels from headings
- Investigation Map Preview: lighter borders, muted text, subtle background to signal provisional state
- Turn history cards: removed redundant subheadings ('Your answer', 'What changed') and divider lines
- Button label: 'Update situation' → 'Update'; padding consistent with design tokens
- Condition clarity fix: '!hasSelectedQuestion === false' → 'hasSelectedQuestion'
- Workspace polish section added to UX guidelines
robbond
2f87cca88d