Add aria-pressed/aria-selected to onboarding selection cards

[Abidoyesimze]

Summary

StrategyOverviewStep and FirstDepositStep's selection cards are correctly keyboard-operable (role="button" tabIndex={0} + Enter/Space handling) but neither sets aria-pressed/aria-selected to reflect which option is currently chosen — only a visual border/dot indicates selection. The equivalent StrategySelector component already does this correctly via aria-pressed={isSelected}.

Affected files

• src/components/onboarding/steps/StrategyOverviewStep.tsx
• src/components/onboarding/steps/FirstDepositStep.tsx
• src/components/strategies/StrategySelector.tsx

Tasks

• Add aria-pressed={isSelected} (or aria-selected, whichever fits the role used) to both onboarding step components, matching StrategySelector's existing pattern.

Acceptance criteria

• Scope is limited to the files listed (or agreed alternatives in the PR).
• Change is verifiable: tests, screenshots, or written QA steps in the PR.
• No behavior regressions in related user flows.
• No new duplicate abstractions without a one-line rationale in the PR.

Suggested labels

a11y, onboarding

Notes

Sourced from the 2026-08 round-4 follow-up audit of the frontend codebase at commit 201f5b0, run after the round-3 batch (#684-#743) was substantially resolved. Verified against current file content at time of writing.